refactor!: rebrand CCAM to AgentHub

Clean break, no compatibility alias. Renames the product name, the CLI
binary (`ccam` -> `agenthub`), the env var prefix (`CCAM_` ->
`AGENTHUB_`), the Prometheus metric namespace (`ccam_*` ->
`agenthub_*`), the tmux session prefix (`ccam-lane-<id>` ->
`agenthub-lane-<id>`), the per-repo runtime profile directory
(`.ccam/profile` -> `.agenthub/profile`), the lanes state root
(`~/.claude/ccam-lanes` -> `~/.claude/agenthub-lanes`), the bundled
plugins (`plugins/ccam*` -> `plugins/agenthub*`) and their slash
commands (`/ccam-doctor` -> `/agenthub-doctor`, `/ccam:*` ->
`/agenthub:*`).

Because there is no alias, an existing install has to be updated by
hand: rename its `.ccam/profile` directory and any `CCAM_*` variables,
and reinstall the plugin under its new name.

Two other name families are deliberately left alone here, since they are
not just strings: the `Claude-Code-Monitor` repository/marketplace name,
and the `agent-dashboard` npm package plus its `~/.claude/agent-dashboard`
runtime directory, which holds the live database and needs a migration
rather than a rename.

Verified: server 1406/1406, client 459/459, `grep -i ccam` clean across
tracked files, `openapi.yaml` regenerated (95 paths, unchanged count).

plugins/agenthub/commands/ship-quick.md

@@ -0,0 +1,23 @@
+---
+description: Run the 8-stage in-repo pipeline (plan → implement → tests → review → gate → ship). No PR, no browser QC
+argument-hint: <requirement>
+allowed-tools: Bash(agenthub lanes pipeline:*)
+---
+
+Put this lane on the 8-node `default` template first, so the dashboard renders
+the right node count from the first stage:
+
+!`agenthub lanes pipeline default`
+
+Then run the pipeline **in this session** by invoking `/agenthub:ship-feature` with
+this requirement:
+
+$ARGUMENTS
+
+- No requirement given → ask for one. Never guess what to build.
+- The switch above failed (no lane owns this directory) → say so and stop; the
+  skill has no lane to report stages against.
+
+This is the in-session twin of `agenthub ship-quick "<requirement>"`. It stops at
+review/gate: no PR is opened and no browser QC runs — use `/ship-full` when the
+work should reach reviewers.