feat(ship-check): add --model flag, default agents to inherit session model

plugins/ship-check/agents/bug-checker.md

@@ -7,7 +7,7 @@ description: >
   a deep correctness check or to look for subtle bugs, and verifying that tool
   descriptions match their implementations after changes. See "When to invoke" in the
   agent body for worked scenarios.
-model: opus
+model: inherit
 color: red
 tools:
   - Read

plugins/ship-check/agents/code-quality-reviewer.md

@@ -7,7 +7,7 @@ description: >
   conventions), a user asking for a convention-grounded code quality pass, and reviewing
   changed files against project-specific naming and immutability rules. See "When to
   invoke" in the agent body for worked scenarios.
-model: opus
+model: inherit
 color: green
 tools:
   - Read

plugins/ship-check/agents/pr-reviewer.md

@@ -7,7 +7,7 @@ description: >
   convention-aware PR review rather than a generic one, and reviewing a PR against
   project-specific TDQS scoring or feature surface doc requirements. See "When to invoke"
   in the agent body for worked scenarios.
-model: opus
+model: inherit
 color: cyan
 tools:
   - Read

plugins/ship-check/agents/test-auditor.md

@@ -6,7 +6,7 @@ description: >
   for Phase 3, a user asking to audit tests or check test quality against conventions,
   and checking whether production code changes have adequate test coverage. See "When
   to invoke" in the agent body for worked scenarios.
-model: opus
+model: inherit
 color: yellow
 tools:
   - Read

plugins/ship-check/skills/ship-check/SKILL.md

@@ -278,6 +278,7 @@ Dispatch the `pr-reviewer` agent type from the ship-check plugin:
 ```
 Agent({
   subagent_type: "ship-check:pr-reviewer",
+  model: "<model>",  // include ONLY when --model is specified
   description: "PR review — correctness, security, conditional checks",
   prompt: "Review the PR on branch <branch> (PR #<number>) against main. This is Phase 1 of the ship-check pipeline — focus on dimensions 1 (correctness), 4 (security/performance), and conditional dimensions 5-7 (TDQS, feature surface docs, stale path references). Skip dimensions 2 (conventions) and 3 (test quality) — dedicated agents handle those next. Fix all high/medium confidence findings directly. For low-confidence findings: fix if the change is trivial and safe (< 5 lines, no interface change); only flag when the fix itself is uncertain, risky, or needs a design decision. When flagging, categorize as: 'uncertain diagnosis', 'complex fix', or 'needs design decision'. Commit and push."
 })
@@ -295,6 +296,7 @@ Dispatch the `code-quality-reviewer` agent type:
 ```
 Agent({
   subagent_type: "ship-check:code-quality-reviewer",
+  model: "<model>",  // include ONLY when --model is specified
   description: "Code quality — conventions, readability",
   prompt: "Run a code quality pass on branch <branch> (PR #<number>) against main. Review all changed files (source, CI/CD, IaC, config — everything except test files) for naming, structure, comments, simplicity, and module conventions; changed markdown docs get the docs & comment concision dimension. Fix every finding, commit, and push. Prior-phase context: <summarize what Phase 1 fixed and any deferred findings>."
 })
@@ -310,6 +312,7 @@ Dispatch the `test-auditor` agent type:
 ```
 Agent({
   subagent_type: "ship-check:test-auditor",
+  model: "<model>",  // include ONLY when --model is specified
   description: "Test audit — quality + coverage gaps",
   prompt: "Audit tests on branch <branch> (PR #<number>) against main. Audit all changed test files against convention dimensions AND run coverage gap analysis on changed non-test files. Write missing tests for coverage gaps. Fix test quality issues. Commit and push. Prior-phase context: <summarize what Phases 1-2 fixed and any deferred findings>."
 })
@@ -325,6 +328,7 @@ Dispatch the `bug-checker` agent type:
 ```
 Agent({
   subagent_type: "ship-check:bug-checker",
+  model: "<model>",  // include ONLY when --model is specified
   description: "Bug check — 7-dimension systematic hunt",
   prompt: "Run a systematic bug check on branch <branch> (PR #<number>) against main. Read every changed file in full (source, CI/CD, IaC, config — all non-test files). Apply all 7 dimensions — especially dimension 1 (description-vs-implementation, quote verbatim). Fix high-confidence bugs directly. For medium/low-confidence findings: fix if the change is trivial and safe (< 5 lines, no interface change); only flag when the fix itself is uncertain, risky, or needs a design decision. When flagging, categorize as: 'uncertain diagnosis', 'complex fix', or 'needs design decision'. Commit and push. Prior-phase context: <summarize what Phases 1-3 fixed and any deferred findings>."
 })
@@ -423,6 +427,11 @@ The user can customize the pipeline:
 - `/ship-check --comment` — post findings as inline PR review comments instead of fixing.
   Implies --no-fix. Phase 5 (pr-monitor) is skipped — the pipeline is reviewing a PR it
   isn't responsible for. Composable with --skip, --only, --inline, --fork.
+- `/ship-check --model <name>` — override the model for all phase agents. Valid values:
+  `sonnet`, `opus`, `haiku`, `fable`. Overrides the agent definition's `model:` frontmatter
+  for this run only. Useful for forcing a specific tier (`--model opus` for thoroughness)
+  when the session is on a different model. Ignored with `--inline` (inline phases use
+  the session's model). Default: `inherit` (agents use the session's model).
 - `/ship-check --inline` — run all phases in the current context (no agents, no fresh
   eyes — useful when context from prior work is actually helpful)
 - `/ship-check --fork` — use forks instead of agents (legacy behavior — spawns forks