Group the sources into aliased modules and lint with the published plugins (#23)

Groups the flat `src/` into cohesive modules and turns on the published lint plugins. No behavior change.

## Module layout

Each module is a direct `src/` subfolder with an `index.ts` barrel and a `#` alias in `package.json` `imports` (layer order, top first):

| Alias | Files |
| --- | --- |
| `#prepare` | `index.ts` (the prepare phase entry point) |
| `#run` | `index.ts` (the run phase entry point) |
| `#post` | `index.ts` (the post phase entry point), `post.ts`, `post.test.ts` |
| `#agents` | `auth.ts`, `opencode.ts` (Codex / Claude Code sign-in, OpenCode args and output) |
| `#processes` | `child.ts`, `isolation.ts` |
| `#runtime` | `runtime.ts`, `credentials.ts` |
| `#profiles` | `profiles.ts` |
| `#common` | `errors.ts`, `json.ts` |
| `#testing` | `index.ts` (unchanged) |

Every top-level entry of `src/` is an aliased module folder. Tests stay next to their code as `*.test.ts`. Each phase's `index.ts` is its entry point, and `action.yml` now runs `node src/<phase>/index.ts`. The post phase's logic moved to `src/post/post.ts` so its test can import it; `index.ts` keeps the env reading and the `import.meta.main` call. `run`'s prompt URL is now `../../prompt.md`. `scripts/protect-source.sh` now copies `src/` recursively (it used to copy `src/*.ts` only), and the workflow test checks that module files get staged too.

## Lint plugins

- New devDependencies: `eslint-plugin-explicit-types@^0.6.1` and `eslint-plugin-import-structure@^0.10.2`, both in `jsPlugins`. The lockfile comes from a real `npm install`.
- Enabled configs: `importStructure.configs.modules`, `explicitTypes.configs.concrete`, `explicitTypes.configs.absence`.
- **explicit-types `naming` is off** (the other app repos turn it on). Its `upper-snake-string-unions` and `no-upper-snake-object-keys` rules fire on wire tokens this repo doesn't choose: profile types `"claude" | "codex" | "opencode"` from `profiles.json`, failure reasons posted to Gitea, Gitea's `"new" | "old"` side, and environment variable names such as `PATH`. Satisfying them would change behavior or need opt-outs. This is logged as an open question for the user.

Lint fixes, all type-level:
- `Pick<BotProfile, "type" | "model">` became a named `ProfileIdentity` interface that `BotProfile`, `ProfileFailure`, and `RuntimeProfile` extend. `RuntimeOutcome` is now `RuntimeSuccess | RuntimeFailure`.
- Inline object types became named interfaces.
- `Record<string, string>` env maps became `NodeJS.ProcessEnv`. `JsonObject` and the verdict table became `NodeJS.Dict<…>`.
- `T | undefined` locals and returns became `T | null` with matching checks. `typeof fetch` became a `Fetcher` type.
- Claude's result fields are held in camelCase (`isError`, `apiErrorStatus`) after parsing, because `id-match` rejects snake_case interface members.
- Duplicate import sources are merged (`import-structure/no-duplicate-import-source`).

## Verification

- `vp check`: clean.
- `vp test`: 61 passed and 5 skipped as a normal user. All 66 passed as root in `node:24-bookworm`.
- Each phase (`node src/<phase>/index.ts`) run from a `protect-source.sh` copy loads its full alias graph under Node.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Reviewed-on: #23
Reviewed-by: bot <noreply@capsulizers.com>
Co-authored-by: Danny Kim <temeddix@gmail.com>
Co-committed-by: Danny Kim <temeddix@gmail.com>

package.json

@@ -4,12 +4,22 @@
   "description": "A Gitea composite action that runs a coding agent for approved issue and pull request automation.",
   "type": "module",
   "imports": {
+    "#prepare": "./src/prepare/index.ts",
+    "#run": "./src/run/index.ts",
+    "#post": "./src/post/index.ts",
+    "#agents": "./src/agents/index.ts",
+    "#processes": "./src/processes/index.ts",
+    "#runtime": "./src/runtime/index.ts",
+    "#profiles": "./src/profiles/index.ts",
+    "#common": "./src/common/index.ts",
     "#testing": "./src/testing/index.ts"
   },
   "devDependencies": {
     "@eslint/core": "^0.17.0",
     "@types/node": "^24.19.2",
     "@typescript-eslint/types": "^8.71.2",
+    "eslint-plugin-explicit-types": "^0.6.1",
+    "eslint-plugin-import-structure": "^0.10.2",
     "vite-plus": "^1.2.0",
     "yaml": "^2.9.1"
   }