refactor: rename Gitea environment variables to CI registry prefix

update SETUP.md and .env.example

SETUP.md

@@ -12,6 +12,7 @@ This guide covers prerequisites, environment setup, running the application loca
 - **Git**: For cloning and version control.
 - **Cloudflare Account**: For R2 storage and CDN (free tier sufficient for most use cases).
 - **Gitea Account**: Required if you want to push images to the self-hosted registry or use the repository's CI/CD flow.
+  - Create new secrets in Gitea: Settings → Secrets → Actions, add `CI_REGISTRY_USER` (username) and `CI_REGISTRY_TOKEN` (token with `write:packages` scope)
 - **Hetzner Cloud Account** (optional for production): For the US-East VPS (Ashburn, VA recommended per ADR-001).
 
 ## Development Prerequisites
@@ -70,10 +71,12 @@ This guide covers prerequisites, environment setup, running the application loca
    # VITE_PUBLIC_HLS_URL=http://localhost/hls/playlist.m3u8
 
    # Gitea Container Registry (for self-hosted Docker images)
-   GITEA_REGISTRY_URL=git.allucanget.biz
-   GITEA_USERNAME=your-gitea-username
-   GITEA_TOKEN=your-gitea-token
-   GITEA_REGISTRY_NAMESPACE=zwitschi/linearvoid
+   CI_REGISTRY_URL=git.allucanget.biz
+   CI_REGISTRY_USER=your-gitea-username
+   CI_REGISTRY_TOKEN=your-gitea-token
+   CI_REGISTRY_NAMESPACE=zwitschi/linearvoid
+   # Gitea API access (optional, for CI/release automation)
+   CI_SERVER_URL=https://git.allucanget.biz
 
    # Chat / Database
    DATABASE_URL=postgres://linearvoid:linearvoid@db:5432/linearvoid?sslmode=disable
@@ -99,11 +102,6 @@ This guide covers prerequisites, environment setup, running the application loca
    # Development flags
    NODE_ENV=development
    GO_ENV=development
-
-   # Gitea API access (optional, for CI/release automation)
-   GITEA_SERVER_URL=https://git.allucanget.biz
-   GITEA_TOKEN=your-gitea-token
-   GITEA_USERNAME=your-gitea-username
    ```
 
 4. **Check local value overrides for Docker Compose**:
@@ -162,12 +160,12 @@ This guide covers prerequisites, environment setup, running the application loca
 
 2. **Create an access token**:
    - Generate a token with the scopes needed for package/registry access and, if applicable, repository automation.
-   - Store it as `GITEA_TOKEN` in `.env`.
+   - Store it as `CI_REGISTRY_TOKEN` in `.env`.
 
 3. **Configure registry variables**:
-   - Set `GITEA_REGISTRY_URL` to the Gitea host.
-   - Set `GITEA_REGISTRY_NAMESPACE` to the image namespace, for example `zwitschi/linearvoid`.
-   - Set `GITEA_USERNAME` to the account that will push or pull images.
+   - Set `CI_REGISTRY_URL` to the Gitea host.
+   - Set `CI_REGISTRY_NAMESPACE` to the image namespace, for example `zwitschi/linearvoid`.
+   - Set `CI_REGISTRY_USER` to the account that will push or pull images.
 
 4. **Authenticate Docker to the registry**:
 
@@ -260,7 +258,7 @@ This guide covers prerequisites, environment setup, running the application loca
    ```
 
 5. **Publish or verify required images in Gitea**:
-   - Ensure the `playout`, `chat`, and `nginx` images exist under `${GITEA_REGISTRY_URL}/${GITEA_REGISTRY_NAMESPACE}`.
+   - Ensure the `playout`, `chat`, and `nginx` images exist under `${CI_REGISTRY_URL}/${CI_REGISTRY_NAMESPACE}`.
    - Log in to the registry from the VPS before pulling.
 
 6. **Deploy the production stack**: