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-workflows/skills/delegation-audit/SKILL.md

@@ -0,0 +1,55 @@
+---
+description: >
+  Audit model delegation and subagent effectiveness for a session — which
+  models handled which subagent types, per-type success rates and average
+  durations, and wasted delegations (heavy models on trivial work or types
+  that consistently fail) — using the Agent Monitor workflow intelligence API.
+  Use when reviewing how a session delegated work across models and subagents.
+---
+
+# Delegation Audit
+
+Audit how a Claude Code session delegated work: model-to-subagent mapping and whether each delegation paid off.
+
+## Input
+
+The user provides: **$ARGUMENTS**
+
+A session ID. If empty, fetch `GET /api/sessions?limit=1` and audit the most recent session, stating which one.
+
+## Data Sources
+
+| Endpoint | Returns |
+|----------|---------|
+| `GET /api/workflows/{sessionId}` | The `modelDelegation` dataset (which models are delegated which subagent types) and the `effectiveness` dataset (per-type completion/success rate, avg duration, task success) |
+| `GET /api/agents` | Raw subagent records (`type`, `model`, `status`, `depth`, `parent`) to corroborate counts and statuses |
+
+## Report Sections
+
+### 1. Delegation Matrix
+From `modelDelegation`: a model × subagent-type table of how many agents of each type each model ran.
+| Model | explore | code-review | debugger | ... | Total |
+|-------|---------|-------------|----------|-----|-------|
+
+### 2. Effectiveness by Subagent Type
+From `effectiveness`: per type, the success rate and average duration.
+| Subagent type | Count | Success rate | Avg duration | Verdict |
+|---------------|-------|--------------|--------------|---------|
+Mark types below ~70% success as low-yield.
+
+### 3. Wasted Delegations
+Flag, with evidence:
+- A heavy model (e.g. Opus) assigned to a simple/low-stakes subagent type that a cheaper model handled successfully elsewhere — candidate for rebalancing.
+- Subagent types with low success rates (effort spent, task not completed).
+- Duplicate delegations: the same type spawned repeatedly with poor success (retry churn).
+
+### 4. Rebalancing Suggestions
+Concrete model reassignments grounded in the matrix and effectiveness data. State the type, the model used, the success rate, and the suggested model — only where the data supports it.
+
+## Output
+
+- Markdown tables for the matrix and effectiveness.
+- Success rates as percentages; durations in human units (e.g. `1m 12s`).
+- Use ▲/▼ when comparing a type's success rate against the session-wide average.
+- Cite only numbers returned by the API; do not infer success rates that the `effectiveness` dataset does not provide.
+- If the dashboard is unreachable, tell the user to start it with `npm start` from the repo root.