chore: v5 prep — dep bumps, linux64 extension, legacy CLI removal, Cli→PluginOptions rename (#837)

* fix: remove concurrency block from reusable workflow to prevent deadlock

When integrity-check.yml calls validate-orchestrator-integration.yml via
workflow_call, both workflows resolve github.workflow to the same name
("Integrity"), creating identical concurrency groups. GitHub detects this
as a deadlock and cancels the run.

Fix: remove concurrency from the reusable workflow entirely — the caller
already manages concurrency for the group.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

* feat: add linux64RemoveExecutableExtension parameter (default: false)

Adds configurable control over the `.x86_64` file extension for
StandaloneLinux64 builds. Default is `false` (keep the extension),
matching Unity's native behavior.

Set `linux64RemoveExecutableExtension: true` to restore the
extensionless behavior from v4.

Rebased from kitlith's original PR #726. Default flipped for v5.

Closes #722

Co-Authored-By: kitlith <kitlith@users.noreply.github.com>
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

* chore: bump production dependencies (minor/patch)

- @actions/cache ^4.0.0 → ^4.1.0
- @actions/github ^6.0.0 → ^6.0.1
- commander ^9.0.0 → ^9.5.0
- nanoid ^3.3.1 → ^3.3.12
- reflect-metadata ^0.1.13 → ^0.2.2
- semver ^7.5.2 → ^7.7.4
- yaml ^2.2.2 → ^2.8.4

All minor/patch bumps. Major bumps (@actions/core 3.x, nanoid 5.x ESM)
deferred to a separate PR.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

* chore: remove legacy CLI bootstrap and unused deps

Remove InitCliMode/RunCli, @CliFunction decorator, and
CliFunctionsRepository. The only registered CLI mode was `print-input`
which is unused — all real CLI functionality lives in the orchestrator
repo now.

This drops 3 dependencies:
- commander-ts (decorator-based CLI, needed reflect-metadata)
- reflect-metadata (peer dep of commander-ts)
- commander (only used for OptionValues type)

Cli.options, Cli.isCliMode, and Cli.query remain — the orchestrator
plugin sets these directly without commander.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

* refactor: rename Cli to PluginOptions, remove cli directory

Cli class was a legacy name from when unity-builder had its own CLI.
Now it's just an options bridge for plugins — renamed to PluginOptions
with a backwards-compatible Cli alias for the orchestrator.

Moved from src/model/cli/cli.ts to src/model/plugin-options.ts.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

* fix(ci): fix orchestrator integration test failures

Two issues:
1. jest → vitest: the repo migrated to vitest but the integration
   workflow still called `npx jest`. Changed to `npx vitest run`.

2. Git checkout corruption: when the orchestrator branch matching the
   PR doesn't exist, the first checkout fails leaving a corrupted .git
   directory. The fallback step then hits `fatal: ambiguous argument
   'HEAD'`. Fix: add `clean: true` to all fallback checkout steps so
   they wipe the broken state before re-cloning.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

* fix(ci): wipe .git before fallback checkout, fix remaining jest syntax

- Add `rm -rf .git` step before fallback checkout to clear corrupted
  state when branch-matching checkout fails
- Fix unit test step: replace jest --testPathPattern with vitest
  positional filters (same fix as orchestrator PR #18)
- Replace all --detectOpenHandles --forceExit --runInBand with
  vitest --no-file-parallelism

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

* refactor: simplify plugin mode check

---------

Co-authored-by: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Co-authored-by: kitlith <kitlith@users.noreply.github.com>

src/model/input.ts

@@ -1,6 +1,6 @@
 import fs from 'node:fs';
 import path from 'node:path';
-import { Cli } from './cli/cli';
+import { PluginOptions } from './plugin-options';
 import Platform from './platform';
 import GitHub from './github';
 import os from 'node:os';
@@ -28,8 +28,8 @@ class Input {
     const alternativeQuery = Input.ToEnvVarFormat(query);
 
     // Query input sources
-    if (Cli.query(query, alternativeQuery)) {
-      return Cli.query(query, alternativeQuery);
+    if (PluginOptions.query(query, alternativeQuery)) {
+      return PluginOptions.query(query, alternativeQuery);
     }
 
     if (process.env[query] !== undefined) {
@@ -284,6 +284,12 @@ class Input {
     return Input.getInput('skipActivation')?.toLowerCase() ?? 'false';
   }
 
+  static get linux64RemoveExecutableExtension(): boolean {
+    const input = Input.getInput('linux64RemoveExecutableExtension') ?? 'false';
+
+    return input === 'true';
+  }
+
   public static ToEnvVarFormat(input: string) {
     if (input.toUpperCase() === input) {
       return input;