Replace deploy scripts with self-contained compose bootstrap jobs

Removes every wrapper script under deploy/ (up.ps1, up.sh, scripts/*,
zitadel/provision.*) and folds their logic into three one-shot services
in compose.yml, following the pattern already used by seaweedfs-init:

  keys-init     generates the RS256 stream-ticket key pair
  migrate       applies the EF Core migrations (backend/Musify.Migrator.Dockerfile)
  zitadel-init  creates the Musify project + OIDC apps, writes the client
                ids back into the active env file

Deploying is now two plain `docker compose` commands, no scripts to run
or chmod:

  docker compose -f deploy/compose.yml -f deploy/compose.dev.yml up -d
  docker compose -f deploy/compose.yml -f deploy/compose.dev.yml --profile apps up -d --build

(swap compose.dev.yml for compose.prod.yml + --env-file deploy/.env.prod
for production). The first command brings up infra and lets the bootstrap
jobs run to completion; the second builds and starts the apps, which by
then read real OIDC values instead of empty ones — compose interpolates
${VAR} once per invocation, so this can't collapse into a single command
without the apps reading their own config file at container start instead
of via compose env (out of scope here).

Also:
- DatabaseDesignTimeFactory now also reads Database__ConnectionString
  from the environment, and DesignSettings.json is optional, so the new
  migrate container works without user-secrets or a config file excluded
  from the Docker build context by .dockerignore.
- nginx's depends_on no longer lists the apps-profile services: it does
  not need them at its own startup (every vhost resolves its upstream at
  request time via the embedded Docker resolver), and requiring them made
  `compose.prod.yml up -d` (without --profile apps) an invalid project.
- env_get/env_set in zitadel-init strip \r: the mounted env file can have
  CRLF line endings on Windows, which otherwise makes an empty-looking
  value non-empty to `[ -z ... ]`. .env.example/.env.prod.example are
  pinned to LF via .gitattributes for the same reason. Also fixed:
  rewriting the bind-mounted env file in place instead of renaming a temp
  file over it (rename onto a bind-mounted inode fails with "Resource
  busy").
- Removed compose.share.yml and zitadel/.output-share/ — a "temporary"
  personal overlay that had leaked a real Zitadel service-account PAT
  into git history (committed in 70968b3). That token should be rotated.
- Removed deploy/.tmp/ from .gitignore: nothing mounts or creates it
  anymore (it never actually did, either — no compose service referenced
  it, only the now-removed up.ps1 did).

Verified end-to-end with Docker: a clean `down -v` + fresh `up -d` +
`--profile apps up -d --build` on the dev stack brings up all four one-shot
jobs successfully and all four apps healthy (api/gateway return 200,
worker starts its consumers with no errors, web-player responds). Also
verified compose.prod.yml starts nginx cleanly with dummy certs and no
apps running, confirming the depends_on fix.

web-player/.env.example

@@ -1,5 +1,6 @@
-# Local configuration for `npm run dev`. deploy/zitadel/provision.ps1 fills in
-# the Zitadel values; in Docker the same variables come from deploy/compose.yml.
+# Local configuration for `npm run dev`. Copy the WEB_CLIENT_ID /
+# WEB_CLIENT_SECRET that deploy/compose.yml's zitadel-init service writes to
+# deploy/.env; in Docker the same variables come from deploy/compose.yml.
 
 # Zitadel OIDC (server-side auth)
 ZITADEL_ISSUER=http://host.docker.internal:8080

web-player/README.md

@@ -12,10 +12,10 @@ npm install
 npm run dev      # :5173
 ```
 
-Configuration lives in `.env` (template in `.env.example`).
-`deploy/zitadel/provision.ps1` fills in the Zitadel values automatically, so the
-usual flow is to bring the stack up first (`./deploy/up.ps1`) and then run the
-dev server.
+Configuration lives in `.env` (template in `.env.example`). Bring the
+infrastructure stack up first (see [../deploy/README.md](../deploy/README.md))
+and copy the `WEB_CLIENT_ID` / `WEB_CLIENT_SECRET` it writes to `deploy/.env`
+into this `.env` once, then run the dev server.
 
 ```sh
 npm run check    # svelte-check — must be clean before closing a change