feat(lifeboard): Activity — what changed, who changed it, and undo

[ivanmkc]

The stack

#	PR	What it adds	Tests at this point
1	#311	A real localStorage for the test suite on Node 25	viewer 747
2	#312	@ivanmkc/termchart-canvas; injectable interact transport	canvas 473 · viewer 278
3	#313	lifeboard PWA: fact log, boards, service worker	lifeboard 36
4	#314	Shell, family profiles, tap layer	lifeboard 82
5	#315	The agent turn, four providers, Connections	lifeboard 142
6	#316	Packs, recipes, shopping-list arithmetic	lifeboard 231
7	#317	Provenance and lineage	lifeboard 257
8	#318	Calendar, Gmail, mail triage	lifeboard 301
9	#319	The bridge and long jobs	cli 314 · lifeboard 320
10	#310	Proactivity, scheduled boards, Google sign-in	cli 320 · lifeboard 343
11	#320	Persistence audit fixes: multi-tab, stale builds, no-storage boot	lifeboard 350
12	#321	User guide, bridge setup, QA guide, persistence audit	lifeboard 350
13	#322	A plan for third-party integrations (docs only)	unchanged
14	#323	A practice drill a board can define: audio + Q&A	canvas 485 · lifeboard 372
15	#325	Export and restore	lifeboard 389
16	#326	Draft a message, approve it, then send	lifeboard 399
17	#327	Hand long work to the Mac	lifeboard 406
18	#328	A Packs screen, and authoring one by describing it	lifeboard 418
19	#329	Activity — what changed, who changed it, undo	lifeboard 428

Every branch in the stack was checked out on its own and verified independently: npm install, tsc --noEmit for every package, npm test across the workspace, and the offline e2e where it exists. All nineteen are green — no branch depends on a later one to build or pass. Full viewer e2e (11 suites, 106 assertions) was run on #312 as the behaviour-preservation evidence for the extraction.

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Stack position: 19 of 19 — the top of the stack. Base: lifeboard/17-packs-ui.

The log has recorded this since the first commit; every entry already says who and when. This is the view over it, and it is the screen that makes the whole design legible: a household can see that the assistant changed four things overnight, which four, and take any of them back.

Undo is offered only on the latest change to a record. Reverting an older one would restore a value that two later changes have already moved past — it looks like undo and is silent data loss. Older entries say "superseded", and the shell refuses the action even if the link is constructed by hand.

Reached from Sources rather than the rail: Sources answers "where did this come from?" and Activity answers "what changed?" — two questions about the same log, and eleven rail items is already enough.

Verified: lifeboard 428 (+10), offline e2e extended to walk Sources → Activity and confirm the seeded changes are attributed to code rather than to a person.

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⚠️ See #324 — an audit of the deck against what is built and what is tested, filed after this branch. It found four documented-but-absent features and six more capabilities that are tested with no runtime caller.