docs(landing): bring the docs site to 0.10 parity

[enekos]

The docs page had drifted several releases behind the framework. This is a docs-only change — landing/src/Docs.svelte and landing/src/Landing.svelte, nothing under crates/.

Things that were wrong, not just missing

Claim on the site	Reality
ai is a default feature	Removed in 0.6.0; the tool surface is always-on core
Queue is "Postgres-backed, cross-pod"	Runs on any Backend since 0.9.0
Queue::new(pool), handler takes |payload|	Queue::new(store), handler takes &JobCtx
Pg::from_env()	Takes a pool size: Pg::from_env(8)
Migrations are hand-written closures	The diff/generate/drift workflow was entirely absent
362 KB core binary	394 KB measured

Pillars that had no documentation at all

WebSockets · PubSub · channels & presence · actors & supervision · the REPL · relations · JSON path queries · full-text & hybrid search · embeddings & vector search · reactive queries · backend capabilities · row locks / isolation / RETURNING / bulk insert · advisory locks · collections · crypto · static files · credentialed CORS · ops_guard · App::listener

Internals & options

These existed only in the source. Added: the request lifecycle and guard ordering, why keep-alive is capped twice, the two slowloris deadlines, panic isolation and its panic = "abort" caveat, how an upgrade detaches from the worker, where ~394 KB comes from — plus tables for every Limits and WsConfig field with its default, the per-backend capability matrix, the feature matrix, and the 22-crate workspace map.

53 sections in 7 groups, up from 30 in 6.

Verification

• pnpm run build clean; svelte-check 0 errors / 0 warnings.
• Headless render: 53 nav links against 53 article anchors, 0 broken deep-links; no horizontal page overflow (scrollWidth == clientWidth); all six escaped-brace literals ({{ escaped }}, {a,b,0}, …) render as literal braces.
• pnpm run check still exits non-zero, but on a pre-existing vite.config.ts error — Vite 8 dropped brotliSize. Untouched here; worth a separate one-line fix.

Note for the reviewer

The "Responses & errors" section documents 5xx bodies being redacted to {"error":"internal error"}. That behaviour is in e2a6fd8, which is still unpushed on local master — this section becomes accurate the moment that commit lands.

Out of scope, still stale: README.md lists 11 of 22 crates, and its Status "Next:" line names keep-alive, form-encoded bodies and relations, all of which have shipped.