### What?
Bump the plugin template's pinned Payload package versions from `3.37.0`
to `3.82.1` and add it to `generate-template-variations.ts` so future
releases bump it automatically.

### Why?
Audit against the current Payload version (`3.82.1`):

| Template | Payload version | Status |
|---|---|---|
| `blank`, `ecommerce`, `website` | `workspace:*` | ✅ auto-bumped |
| `with-cloudflare-d1`, `with-postgres`, `with-vercel-*` | `3.82.1` | ✅
bumped via release workflow / manual PRs |
| `plugin` | `3.37.0` | ❌ stale (~45 patches behind) |

The plugin template is not a standard app-template variation, so
`generate-template-variations.ts` skipped it entirely. The post-release
workflow therefore never touched it, and the recent manual bump PRs
(#16212, #16229) only covered app templates.

### How?
1. `templates/plugin/package.json` — bump `payload` + `@payloadcms/*`
devDeps from `3.37.0` → `3.82.1`, bump `@payloadcms/eslint-config` from
`3.9.0` → `3.28.0`, bump `peerDependencies.payload` from `^3.37.0` →
`^3.82.1`.
2. `tools/scripts/src/generate-template-variations.ts`:
- Allow `--template plugin` through the filter (plugin isn't a variation
entry).
- After the main loop, call a new `bumpPluginTemplate()` helper which
resolves the latest `payload` version from npm and reuses
`bumpPackageJson`.
- Extend `bumpPackageJson` to also bump `peerDependencies` entries,
writing `^<version>` so plugin consumers can install compatible
patch/minor updates (exact pins would be too strict for a peer dep).

Verified locally with `pnpm script:gen-templates --template plugin` —
picked up the latest npm version (`3.83.0`), bumped devDeps, wrote
`^3.83.0` to peer deps, and preserved `@payloadcms/eslint-config` via
the existing `DO_NOT_BUMP` list.

…oadcms#16212)

- bumps templates to Payload 3.82.0
- removes the --no-server-fast-refresh flag from templates dev script,
as [it is no longer needed with Payload 3.82.0 and Next.js
16.2.2](payloadcms#16202)

---
- To see the specific tasks where the Asana app for GitHub is being
used, see below:
  - https://app.asana.com/0/0/1213983836266021

…#16305)

### What?
Bump the plugin template's pinned Payload package versions from `3.37.0`
to `3.82.1` and add it to `generate-template-variations.ts` so future
releases bump it automatically.

### Why?
Audit against the current Payload version (`3.82.1`):

| Template | Payload version | Status |
|---|---|---|
| `blank`, `ecommerce`, `website` | `workspace:*` | ✅ auto-bumped |
| `with-cloudflare-d1`, `with-postgres`, `with-vercel-*` | `3.82.1` | ✅
bumped via release workflow / manual PRs |
| `plugin` | `3.37.0` | ❌ stale (~45 patches behind) |

The plugin template is not a standard app-template variation, so
`generate-template-variations.ts` skipped it entirely. The post-release
workflow therefore never touched it, and the recent manual bump PRs
(payloadcms#16212, payloadcms#16229) only covered app templates.

### How?
1. `templates/plugin/package.json` — bump `payload` + `@payloadcms/*`
devDeps from `3.37.0` → `3.82.1`, bump `@payloadcms/eslint-config` from
`3.9.0` → `3.28.0`, bump `peerDependencies.payload` from `^3.37.0` →
`^3.82.1`.
2. `tools/scripts/src/generate-template-variations.ts`:
- Allow `--template plugin` through the filter (plugin isn't a variation
entry).
- After the main loop, call a new `bumpPluginTemplate()` helper which
resolves the latest `payload` version from npm and reuses
`bumpPackageJson`.
- Extend `bumpPackageJson` to also bump `peerDependencies` entries,
writing `^<version>` so plugin consumers can install compatible
patch/minor updates (exact pins would be too strict for a peer dep).

Verified locally with `pnpm script:gen-templates --template plugin` —
picked up the latest npm version (`3.83.0`), bumped devDeps, wrote
`^3.83.0` to peer deps, and preserved `@payloadcms/eslint-config` via
the existing `DO_NOT_BUMP` list.