Tactical Media Broadcast Hub — initial release

Self-hosted multi-platform broadcast newsroom for activist collectives:
publishing pipeline with group approval and DST-proof scheduling, TweetDeck-style
column wall with hostile-content-safe rendering, live control room with Auto
Director, bridged chat governance with polls and quorum, distributed sandboxed
transcode workers, encrypted content-addressed archive, monthly analytics.

MIT licensed. See README.md and docs/.

packages/publishing-execution/README.md

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+# Publishing execution
+
+The API and scheduler share this built PostgreSQL repository. Callers own the
+`pg.Pool` and its lifecycle. `scheduleAttempt` and `cancelAttempt` run inside the
+API's existing tenant transaction; other methods establish their own RLS-bound
+transaction. Mutation order is workspace, draft, schedule, attempt, audit.
+
+A business attempt gets a positive decimal attempt number and one provider key.
+Transport retries, Temporal replay and lease recovery retain that key.
+`retryLater` requires proof that the attempt has no unresolved delivery:
+429/refusal of the current request cannot disprove an earlier ambiguous send.
+Use `retryDeduplicated` for that case; it retains dispatch evidence and the
+original dedupe deadline. Both settlements are owner/epoch/expiry fenced.
+Unknown work cannot get a new key or send automatically.
+
+The SDK around-send hook holds `withDispatchGate` across the bounded request,
+after rate-limiter waits. Provider evidence is appended separately before
+finalization, including evidence from stale owners. A current owner can finalize
+a receipt after authorization changes; the audit records those changes. Receipt
+recovery uses a separate workflow ID and never needs another provider send.
+
+Runtime boot never executes owner DDL. Apply migrations through the API's offline
+`migrate` CLI with an explicit `SUPER_DATABASE_URL`; API writes and scheduler
+startup require completed 019, FORCE RLS, valid indexes and the `sp_app` role.
+018 is retained unchanged because local evidence records its application.