wiki: hide low-signal memories + collapse ambient AKC sessions on domain/homepage

Real usage showed two failure modes on /wiki/domains/{tag} and the homepage:

  1. Empty-transcript AKC sessions (mic-off) and synthetic E2E test memories
     competed with real knowledge in topical listings. A user hitting the
     'optics' domain page saw pages of '(no transcript)' and
     'IMG integration test — synthetic session' before finding anything useful.

  2. Every AKC voice session writes an episodic memory as provenance. At
     one session per capture burst these quickly dominate any domain page
     carrying a common tag like 'p05' or 'optics'.

This change partitions memories into three buckets on the domain and
homepage surfaces:
  - low-signal  → hidden entirely (counted in a dim sub-line)
  - AKC session → collapsed behind a single link to /wiki/activity
  - real        → rendered inline

Filter predicates are additive: a memory that's both an empty-transcript
session AND tagged as AKC lands in low-signal (priority).

Tests: 4 new tests in test_wiki_pages.py lock the partition behaviour.
All 15 pre-existing wiki tests still pass.

No schema change, no migration needed.

src/atocore/engineering/wiki.py

@@ -240,10 +240,30 @@ def render_homepage() -> str:
 
     # Quick stats
     all_entities = get_entities(limit=500)
-    all_memories = get_memories(active_only=True, limit=500)
+    all_memories_raw = get_memories(active_only=True, limit=500)
+    # Partition real knowledge from ambient provenance so counts are honest.
+    # Each memory lands in exactly one bucket (low-signal takes priority).
+    all_memories: list = []
+    akc_session_count = 0
+    low_signal_count = 0
+    for _m in all_memories_raw:
+        if _is_low_signal_memory(_m):
+            low_signal_count += 1
+        elif _is_akc_session_memory(_m):
+            akc_session_count += 1
+        else:
+            all_memories.append(_m)
     pending = get_memories(status="candidate", limit=500)
     lines.append('<h2>System</h2>')
-    lines.append(f'<p>{len(all_entities)} entities · {len(all_memories)} active memories · {len(projects)} projects</p>')
+    lines.append(
+        f'<p>{len(all_entities)} entities · {len(all_memories)} memories · '
+        f'{len(projects)} projects'
+        + (f' · <span style="color:#888;">{akc_session_count} AKC session snapshots'
+           + (f", {low_signal_count} low-signal hidden" if low_signal_count else "")
+           + '</span>'
+           if akc_session_count or low_signal_count else '')
+        + '</p>'
+    )
 
     # Triage queue prompt — surfaced prominently if non-empty
     if pending:
@@ -286,6 +306,44 @@ import re as _re
 _WIKILINK_PATTERN = _re.compile(r"\[\[([^\[\]|]+?)(?:\|([^\[\]]+?))?\]\]")
 
 
+# ----------------------------------------------------------------- signal/noise
+# Memories with these patterns are low-signal ambient artefacts — they
+# inflate lists on the homepage and domain pages without being informative.
+# They remain in the DB (for provenance / audit) but are filtered from
+# default browsing surfaces. Pass `include_low_signal=True` on a page query
+# param to surface them.
+_LOW_SIGNAL_CONTENT_PATTERNS = (
+    "(no transcript)",                          # silent-mic AKC sessions
+    "synthetic AKC integration",                # E2E test pollution
+    "AKC-E2E-",                                 # E2E test prefix in content
+    "AKC-IMG-TEST-",                            # image-upload test prefix
+    "IMG integration test — synthetic",         # E2E narrative header
+)
+
+# AKC voice-session ambient memories follow this pattern — they're
+# provenance records, not knowledge. Collapse them behind a link on domain
+# pages instead of rendering each inline.
+_AKC_SESSION_HEADER = "AKC voice session "
+
+
+def _is_low_signal_memory(mem) -> bool:
+    """True for memories whose content is known ambient/test pollution."""
+    content = (getattr(mem, "content", "") or "")
+    if not content:
+        return True
+    return any(p in content for p in _LOW_SIGNAL_CONTENT_PATTERNS)
+
+
+def _is_akc_session_memory(mem) -> bool:
+    """True for AKC voice-session ambient snapshots (have value as provenance,
+    but shouldn't clutter topical listings)."""
+    content = (getattr(mem, "content", "") or "")
+    tags = getattr(mem, "domain_tags", None) or []
+    if any(t in ("session", "akc") for t in tags) and "voice" in tags:
+        return True
+    return content.startswith(_AKC_SESSION_HEADER)
+
+
 def _resolve_wikilink(target: str, current_project: str | None) -> tuple[str, str, str]:
     """Resolve a ``[[Name]]`` target to ``(href, css_class, extra_suffix)``.
 
@@ -874,9 +932,23 @@ def render_domain(tag: str) -> str:
                            breadcrumbs=[("Wiki", "/wiki"), ("Domains", "")])
 
     all_mems = get_memories(active_only=True, limit=500)
-    matching = [m for m in all_mems
+    matching_all = [m for m in all_mems
                     if any((t or "").lower() == tag for t in (m.domain_tags or []))]
 
+    # Partition: low-signal test pollution is hidden entirely, ambient AKC
+    # session memories are collapsed (shown as a count + link to
+    # /wiki/activity). Priority: low-signal > session > real.
+    matching: list = []
+    akc_sessions: list = []
+    hidden_low_signal = 0
+    for m in matching_all:
+        if _is_low_signal_memory(m):
+            hidden_low_signal += 1
+        elif _is_akc_session_memory(m):
+            akc_sessions.append(m)
+        else:
+            matching.append(m)
+
     # Group by project
     by_project: dict[str, list] = {}
     for m in matching:
@@ -884,6 +956,18 @@ def render_domain(tag: str) -> str:
 
     lines = [f'<h1>Domain: <code>{tag}</code></h1>']
     lines.append(f'<p class="meta">{len(matching)} active memories across {len(by_project)} projects</p>')
+    if akc_sessions or hidden_low_signal:
+        noise_bits = []
+        if akc_sessions:
+            noise_bits.append(
+                f'<a href="/wiki/activity">{len(akc_sessions)} AKC voice session snapshots</a>'
+            )
+        if hidden_low_signal:
+            noise_bits.append(f"{hidden_low_signal} low-signal memories hidden")
+        lines.append(
+            f'<p class="meta" style="font-size:0.85rem; color:#888;">'
+            f'Ambient provenance not listed: {" · ".join(noise_bits)}.</p>'
+        )
 
     if not matching:
         lines.append(

tests/test_wiki_pages.py

@@ -161,3 +161,103 @@ def test_memory_detail_shows_superseded_sources(tmp_data_dir):
     assert html1 is not None
     assert "superseded" in html1
     assert "auto-dedup-tier1" in html1  # audit trail shows who merged
+
+
+# -------------------------------------------------- low-signal wiki filters
+# Ambient AKC session memories and test pollution shouldn't dominate domain
+# pages / homepage counts. These tests lock the partitioning behaviour.
+
+def test_domain_page_hides_empty_transcript_sessions(tmp_data_dir):
+    """Silent-mic AKC sessions (content has '(no transcript)') are ambient
+    noise — they go into the hidden count, not the main list."""
+    _init_all()
+    # One real knowledge memory with tag "optics"
+    create_memory(
+        "knowledge",
+        "CGH null corrector supports F/1.2 asphere testing",
+        project="p05", confidence=0.9, domain_tags=["optics", "cgh"],
+    )
+    # One silent AKC session with the same tag — should NOT appear
+    create_memory(
+        "episodic",
+        "AKC voice session abc (gen-002)\nDuration: 60s, 2 captures\n"
+        "\n## Transcript\n(no transcript)\n",
+        project="p05", confidence=0.7,
+        domain_tags=["optics", "session", "akc", "voice"],
+    )
+    html = render_domain("optics")
+    assert "CGH null corrector" in html
+    # The hidden-count banner should be present
+    assert "low-signal" in html or "Ambient provenance" in html
+    # And the empty-transcript content itself is not rendered inline
+    assert "(no transcript)" not in html
+
+
+def test_domain_page_collapses_akc_session_snapshots(tmp_data_dir):
+    """AKC voice-session memories are provenance records — count them as
+    a single collapsed link, don't inline every one."""
+    _init_all()
+    for i in range(5):
+        create_memory(
+            "episodic",
+            f"AKC voice session session-{i} (gen-00{i})\nDuration: 120s, 3 captures\n"
+            f"\n## Transcript\nReal transcript number {i}",
+            project="p05", confidence=0.7,
+            domain_tags=["optics", "session", "akc", "voice"],
+        )
+    html = render_domain("optics")
+    # Inline count should mention AKC session snapshots
+    assert "AKC voice session snapshots" in html
+    # None of the session transcripts should be pasted inline on the domain
+    # page (they're provenance, linked via /wiki/activity)
+    assert "Real transcript number 0" not in html
+
+
+def test_homepage_stats_exclude_ambient_memory(tmp_data_dir):
+    """Homepage system-stats line shows real memory count, pushes ambient
+    counts into a dimmed sub-segment."""
+    _init_all()
+    # 2 real memories + 3 ambient sessions + 1 silent junk
+    create_memory("knowledge", "Real fact 1", project="p05", confidence=0.8)
+    create_memory("knowledge", "Real fact 2", project="p05", confidence=0.8)
+    for i in range(3):
+        create_memory(
+            "episodic",
+            f"AKC voice session s{i} (gen-00{i})\nReal transcript x",
+            project="p05", confidence=0.7,
+            domain_tags=["session", "akc", "voice"],
+        )
+    create_memory(
+        "episodic",
+        "AKC voice session silent (gen-099)\nDuration: 30s, 0 captures\n"
+        "\n## Transcript\n(no transcript)\n",
+        project="p05", confidence=0.7,
+        domain_tags=["session", "akc", "voice"],
+    )
+    html = render_homepage()
+    assert "3 AKC session snapshots" in html
+    assert "low-signal hidden" in html
+    # Main count reflects only real knowledge
+    assert "2 memories" in html
+
+
+def test_low_signal_predicate_catches_known_patterns():
+    from atocore.engineering.wiki import _is_low_signal_memory, _is_akc_session_memory
+    from dataclasses import dataclass
+
+    @dataclass
+    class M:
+        content: str = ""
+        domain_tags: list = None
+
+    # Explicit empty-transcript — low signal
+    assert _is_low_signal_memory(M(content="AKC voice session x\n## Transcript\n(no transcript)\n"))
+    # E2E test pollution — low signal
+    assert _is_low_signal_memory(M(content="IMG integration test — synthetic session"))
+    assert _is_low_signal_memory(M(content="synthetic AKC integration session"))
+    # Real knowledge — NOT low signal
+    assert not _is_low_signal_memory(M(content="The CGH is mounted to the fold mirror via…"))
+    # AKC session tag predicate
+    assert _is_akc_session_memory(M(content="anything", domain_tags=["session", "akc", "voice"]))
+    assert _is_akc_session_memory(M(content="AKC voice session abc"))
+    assert not _is_akc_session_memory(M(content="Real fact", domain_tags=["optics"]))