…CP (#3612)

## Summary

Adds a Region column and Region filter (under More filters) to the runs
list dashboard, the same filter on the public runs list API
(`filter[region]`), and a matching `region` input on the MCP `list_runs`
tool. Each run's executing region is also surfaced as a new optional
`region` field on the runs list and run retrieve responses, populated
from the worker instance group's `masterQueue` identifier.

Useful when you run tasks across multiple regions and want to slice the
runs list — or your existing run-querying scripts — by where the run
actually executed.

## Design

The filter value in the URL / API is the `masterQueue` identifier (the
same string already persisted on `TaskRun` and replicated to ClickHouse
as `worker_queue`), so the query just becomes `worker_queue IN (...)`
with no server-side translation. The Region dropdown options come from a
new resource loader backed by `RegionsPresenter`, which now also exposes
`masterQueue` alongside the existing region metadata.

```ts
// public API
const runs = await runs.list({ region: ["us-east-1", "eu-west-1"] });
// each item: { id, status, ..., region?: "us-east-1" }
```

```ts
// MCP
list_runs({ environment: "prod", region: "us-east-1" })
```

## Summary

Enables shipping `X.Y.Z-rc.N` prereleases of `@trigger.dev/*` via
changesets pre mode. RCs publish under the `rc` npm dist-tag, never
claim `latest`, and don't trigger marketing-site changelog PRs. The
plumbing is hyphen-in-version detection in `release.yml` — no separate
workflow, no opt-in flag at publish time.

Validated end-to-end against a sandbox repo (real npm publishes, Docker
builds, Helm chart pushes, GitHub releases) before porting back. Full RC
lifecycle tested: pre enter → rc.0 → iterate to rc.1 → pre exit →
stable. Plus interaction with the existing release-branch hotfix flow.

## What changes

### `release.yml`
- New `is_prerelease` output (hyphen-in-version)
- GitHub release adds `--prerelease` flag for RC publishes (Pre-release
badge, not Latest)
- `dispatch-changelog` job gated on `is_prerelease != 'true'` — no
marketing-site PR per RC

### Docker workflows
- Removes the `:v4-beta` floating tag entirely from `publish-webapp.yml`
and `publish-worker-v4.yml`. v4 is GA; the tag is a misnomer and is
already inconsistent with the npm side (npm `v4-beta` dist-tag was
frozen at 4.0.4 months ago while Docker `:v4-beta` kept bumping).
Self-hosters should pin to a versioned tag going forward — the last
value of `:v4-beta` stays frozen wherever it currently points.

### CLI version-check fix
(`packages/cli-v3/src/utilities/initialBanner.ts`)
Switches the "new version available" comparison from JavaScript
`localeCompare` to `semver.lt`. The old comparison handled `X.Y.Z-rc.N`
vs `X.Y.Z` incorrectly — a user on `4.5.0-rc.0` would never be prompted
to upgrade once `4.5.0` stable shipped (lex order put the prerelease
ahead of the bare version). Real semver gets this right.

Stable users were never affected: the check queries the `@latest`
dist-tag, which by convention never points at a prerelease.

## How an RC actually publishes after this

1. `pnpm exec changeset pre enter rc` on main, push the `pre.json`
2. Bot regenerates the release PR as `chore: release v<X.Y.Z>-rc.0`
3. Merge → `release.yml` runs `changeset publish` which reads
`pre.json.tag` and publishes under `--tag rc`. GitHub release marked
Pre-release. No marketing-site dispatch.
4. Iterate by adding changesets normally; bot bumps to `rc.1`, `rc.2`, …
5. When ready: `pnpm exec changeset pre exit`, push, merge regenerated
PR → stable ships under `latest` and the marketing-site dispatch fires.

## Summary

Refocuses the v4.5.0 changeset and server-changes content on the
public-facing AI features story, replacing the pre-release-internal diff
framing that had accumulated in `.changeset/` and `.server-changes/`.
Pairs with the RC support PR — the next bot regeneration will pick up
this content.

## What's in here

### Changeset rewrites

- **`chat-agent.md` rewritten as the headline AI Agents entry** —
written from the `docs/ai-chat/` surface (not from internal pre-release
diffs). Covers useChat integration, multi-turn durability via Sessions,
lifecycle hooks, stop generation, tool approvals (HITL), pending
messages + background injection, actions, typed state primitives,
`chat.toStreamTextOptions()`, multi-tab coordination, network
resilience, and the first-turn fast path (`chat.headStart`).
- **New `ai-prompts.md`** — announces the Prompts feature publicly for
the first time. Code-defined templates, deploy-versioning, dashboard
overrides, AI SDK telemetry integration, `chat.agent` integration via
`chat.prompt.set()` + `chat.toStreamTextOptions()`, full management SDK.
- **`sessions-primitive.md` expanded** — calls out
`tasks.triggerAndSubscribe()` and `sessions.list` as standalone
primitives (not just chat.agent infrastructure).
- **`chat-agent-on-boot-hook.md` trimmed** — drops "if you previously…"
pre-release migration framing.
- **Deletes 4 changesets** that described pre-release-internal
migrations or were circular ("groundwork for the upcoming chat.agent" —
chat.agent ships in the same release).

### Server-changes rewrites (`.server-changes/`)

Five new entries for the dashboard surface of the AI feature set:
- Agents list page
- Agent Playground
- Sessions dashboard
- Prompts dashboard (list with usage sparklines + detail with template /
Generations / Metrics / Versions tabs + override UI)
- Models registry (provider-grouped catalog with cross-tenant usage
metrics)
- AI generation span inspector on run traces
- Runs list Task source filter (Standard / Scheduled / Agent)
- Run-detail Agent view (segmented control)

Each entry is 1–2 sentences, no bullets, no implementation file paths —
fits as a single bullet in a future changelog.

Three older `.server-changes/` files were merged or split into the
cleaner taxonomy above and deleted.

## Out of scope

Non-AI-feature server-changes (admin-tabs, queue-length-cap fix,
worker-deployment race, streamdown upgrade, etc.) and changesets
(idempotency-key cap, sigsegv retry, locals-key fix, plugin auth, region
filters, etc.) are untouched.

## Summary

Adds `.changeset/pre.json` to put the repo into changesets pre mode with
dist-tag `rc`. After this merges, the changesets bot regenerates the
existing release PR as `chore: release v4.5.0-rc.0`. Merging that PR
publishes the first release candidate of 4.5.0 to npm under `@rc`.

The pre-mode plumbing landed in #3628. The release content (chat.agent +
sessions + ai prompts + dashboard server-changes) landed in #3629.

## What ships when the bot PR merges

Under dist-tag `rc`:
-
`@trigger.dev/{sdk,core,build,react-hooks,redis-worker,plugins,python,rsc,schema-to-json}@4.5.0-rc.0`
- `trigger.dev@4.5.0-rc.0`

Plus:
- Docker image `ghcr.io/triggerdotdev/trigger.dev:v4.5.0-rc.0`
(immutable tag only — `:v4-beta` is not touched)
- Helm chart `oci://ghcr.io/triggerdotdev/charts/trigger.dev:4.5.0-rc.0`
- GitHub release `v4.5.0-rc.0` marked as Pre-release (no Latest badge)

What does NOT happen:
- npm `latest` stays at 4.4.6
- No marketing-site changelog PR (gated on `is_prerelease != 'true'`)
- Docker `:latest` not touched (we never push it anyway in this repo)

## Iteration

For subsequent rc.N: add a regular changeset to main, bot regenerates
the release PR as `v4.5.0-rc.N`. Merge to ship.

## Exiting pre mode

When ready to ship stable: `pnpm exec changeset pre exit`, push, merge
regenerated PR. That publishes `4.5.0` under `latest` and fires the
marketing-site dispatch.