feat(projects): Wave 1.5 — live emerging-project registration proposals

GET /admin/projects/proposals?min_active=N — on-demand companion to
the nightly scripts/detect_emerging.py cache. Reads SQL + the registry
directly so the result is current.

Each proposal:
  - project_id (literal label as captured)
  - active_count / candidate_count from current SQL
  - sample_memories: 3 most recent active rows with content preview
  - suggested_aliases: sibling labels sharing a >=4-char token,
    case-insensitive (lead-space + lead-space-exploration-ltd +
    space-exploration-ltd cluster; apm and apm-fpga do NOT cluster
    via the 3-char 'apm')
  - guessed_ingest_root: vault:incoming/projects/<id>/

Workflow: hit /admin/projects/proposals to see "what should I register?",
then POST to existing /admin/projects/register-emerging.

For prod: apm has 165 active memories, openclaw has 17,
hydrotech-mining variants combine to 13. apm is overdue.

Closes Codex's prior P2 from the state-of-service review. Reviewed by
Codex on tip e8ac8bb (verdict GO); two follow-on improvements (stronger
negative-clustering test + case-insensitive tokens) folded into f70fa6b.

10 regression tests covering: registered canonical/alias exclusion,
threshold filtering, sibling clustering, short-token negative,
case-insensitive clustering, registered-token-leak guard, sample shape,
candidate counting, param validation, sort order.

Test count: 586 -> 596.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/atocore/api/routes.py

@@ -474,6 +474,33 @@ def api_register_emerging_project(req: RegisterEmergingRequest) -> dict:
     return result
 
 
+@router.get("/admin/projects/proposals")
+def api_project_proposals(min_active: int = 10) -> dict:
+    """Live registration proposals for unregistered projects.
+
+    Reads SQL + the registry directly, so the result is current — unlike
+    `/admin/dashboard.proposals.unregistered_projects` which is the
+    nightly cache from `scripts/detect_emerging.py`. Each proposal
+    includes a guessed ingest root, sibling labels suggested as aliases,
+    and a few sample memories so the operator can sanity-check before
+    POSTing to /admin/projects/register-emerging.
+
+    Query params:
+        min_active: minimum active-memory count for a label to surface
+                    (default 10).
+    """
+    from atocore.memory.service import propose_emerging_projects
+
+    if min_active < 1:
+        raise HTTPException(status_code=400, detail="min_active must be >= 1")
+    proposals = propose_emerging_projects(min_active=min_active)
+    return {
+        "proposals": proposals,
+        "count": len(proposals),
+        "min_active": min_active,
+    }
+
+
 @router.put("/projects/{project_name}")
 def api_project_update(project_name: str, req: ProjectUpdateRequest) -> dict:
     """Update an existing project registration."""