ci(deploy): use correct runner labels and build native binaries

The first run failed with `cargo: command not found` — `runs-on: fedora-43`
is the generic (node) runner, not the Rust toolchain. Split the build:
Rust on `runs-on: rust`, the SPA on `fedora-43` (matching the fleet's
existing conventions, cf. cichlid/helexa workflows).

Also drop the musl static-cross build: the entire fleet is Fedora 43, so
native binaries built on the `rust` runner run on the targets without glibc
skew (deployment-gitea-actions.md §6 permits building on a runner no newer
than the oldest target). Removes the unverifiable musl-toolchain dependency.

Pin pnpm via packageManager so corepack resolves it deterministically.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_016fKZzDpvjiJ9eYbPGgJvUP

web/package.json

@@ -3,6 +3,7 @@
   "private": true,
   "version": "0.1.0",
   "type": "module",
+  "packageManager": "pnpm@10.30.3",
   "scripts": {
     "dev": "vite",
     "build": "tsc --noEmit && vite build",