refactor: move to unified model

[maxy-shpfy]

• refactor: move to unified model
• refactor: connectorRegistry with total resolution
• refactor: Run as an entity
• refactor: Lifecycle-driven revive, reattach, and detached
• refactor: message envelope and server-resolved authorship
• refactor: reaction predicates replace hardcoded routing
• refactor: cross-conversation posts
• refactor: credentials as a connector facet
• feat: a2a agents connector
• refactor: harden remote workers thru shopworld case
• refactor: participant, Membership and Conversation as tables
• refactor: Human Participants, invitation, presence, revocation
• refactor: backend - Room per Conversation
• refactor: Conversation id decoupled from agent id
• refactor: Resource catalog + ResourceReferences tables, backfill, write-through
• refactor: Per-Membership grants + workspace-file catalog entries + web surfacing
• refactor: Multi-party transcript UI
• refactor: A2A peer in a shared room

Code volume summary

Net new production code after comments/blanks: ~8k lines,

Bucket	Insertions	% of 24,434
Drizzle meta/*_snapshot.json (full schema dump × 10)	6,758	27.7%
*.test.ts	5,902	24.2%
Production TS/TSX	11,522	47.2% Of the 11,522 production TS/TSX lines: 7,940 code (68.9%), 2,773 comments (24.1%), 809 blank (7.0%).
Actual SQL (0006–0015)	~145	0.6%
pnpm-lock.yaml	36	0.1%

[maxy-shpfy]

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• poc: workflow debug visualization #82
• refactor: workflow layer #81
• chore: doc update #80
• feat: embed mode of ui #79
• refactor: move to unified model #78 👈 (View in Graphite)
• feat: remote agents #63 : 1 other dependent PR (#64 )
• refactor: extract ui-extensions-sdk #62
• main

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