docs(meta): switch ticket-reference convention #N -> T-N (pql migration phase 3)

Adopts the T-NNN convention (T-N == old #N == pql ticket id) across the active
operational layer: governance/ decision records, .claude/{rules,agents,skills},
CLAUDE.md, DECISIONS.md. 283 references rewritten.

Guarded against false positives (17 correctly skipped, each logged):
  - PR references kept (PR #136/#138/... — PRs are a separate #-namespace)
  - non-ticket numbers kept (#4122; the "#1 process failure" idiom; "task #3")
  - only #N where N is an actual ticket id is rewritten; the 1-4 digit word-bounded
    match also excludes 6-digit hex colours in the visual decision records

Git history is NOT rewritten (a commit's #N already equals T-N numerically), and
historical archives (docs/sprints, docs/discussions, docs/workshops) keep their
point-in-time #N. The /pr-process ticket-ID extraction logic moves to T-NNN in the
Phase 4 consumer cutover.

Verified: pql decisions validate ok; sync 357 records / 1057 refs / broken 0 (the
prose edits don't affect decision parsing or the tickets.decision_ref linkage).
Transform committed at tooling/pql-migrate/retag_ticket_refs.py.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

governance/rejected/economics.md

@@ -4,7 +4,7 @@ Rejected proposals in the **economics** domain, rationale preserved for the audi
 
 ### R-011: Single currency for Phase 2 economics
 - **Rejected:** 2026-04-05
-- **Proposed by:** Burnelli-Sheldon (economist), Sprint 32 Workshop #796 Round 1
+- **Proposed by:** Burnelli-Sheldon (economist), Sprint 32 Workshop T-796 Round 1
 - **Proposal:** Use a single currency for the Phase 2 economics simulation to reduce model complexity; exchange-rate mechanics could be added in a later phase.
 - **Reason:** Three currencies create structural economic bloc tension as an emergent property of initialization, requiring no event generation. The Tractus/Mark divide maps directly to the canonical Assembly vs. Compact political divide. Deferring to a later phase would require retrofitting political geography into a running simulation. Complexity cost low; design value high.
 - **Raised by:** Lead directive overruling the recommendation.

governance/rejected/perception.md

@@ -5,4 +5,4 @@ Rejected proposals in the **perception** domain, rationale preserved for the aud
 ### R-012: Overheard NPC conversation system (D-078) — scrapped
 - **Rejected:** 2026-04-10
 - **Reason:** The entire NPC ambient interaction model (overheard conversations, room grammar, zone-type NPC population, behavior engine for physical spaces) is scrapped. These systems were designed speculatively before a walkable environment exists. The NPC interaction model will be designed and built from scratch after Phase 5 (world generation at tile level) is complete. All content authored against these systems (overheard.ron, zone-type conversation pools) is orphaned. Related content pattern note in content.md and D-078 in perception.md are superseded.
-- **Cross-reference:** D-078 (perception.md), content pattern note (content.md #664)
+- **Cross-reference:** D-078 (perception.md), content pattern note (content.md T-664)