feat(opencode): add session state persistence and documentation

- Added volume mount for ~/.local/state/opencode to persist prompt history and model configuration
- Updated install.sh to ensure ~/.local/state/opencode exists with correct user permissions
- Bumped feature version to 1.0.4
- Created README.md with usage instructions and note on custom user support

Author: zendril

src/opencode/README.md

@@ -0,0 +1,29 @@
+# OpenCode Dev Container Feature
+
+Installs [OpenCode](https://opencode.ai) with persistent configuration and session history.
+
+## Features
+- Installs the `opencode` CLI.
+- Automatically persists:
+    - Authentication (`~/.local/share/opencode/auth.json`)
+    - Session history and storage (`~/.local/share/opencode/storage`)
+    - Global configuration (`~/.config/opencode`)
+    - Prompt history and state (`~/.local/state/opencode`)
+    - Cache (`~/.cache/opencode`)
+
+## Usage
+Add this feature to your `devcontainer.json`:
+
+```json
+{
+  "features": {
+    "ghcr.io/zendril/features/opencode:1": {}
+  }
+}
+```
+
+## Options
+- `version`: Specify the version of OpenCode to install (default: `latest`).
+
+## Note on Custom Users
+Currently, the persistence mounts are hardcoded to `/home/vscode`. If you are using a custom user (e.g., `ubuntu` or a custom username) and need persistence for that user, please open a GitHub issue. We have a planned implementation for dynamic symlinking to support non-standard home directories but have not enabled it yet.

src/opencode/devcontainer-feature.json

@@ -1,6 +1,6 @@
 {
   "id": "opencode",
-  "version": "1.0.3",
+  "version": "1.0.4",
   "name": "OpenCode",
   "documentationURL": "https://opencode.ai/docs/",
   "description": "Installs OpenCode (opencode.ai) with persistent configuration",
@@ -29,6 +29,11 @@
       "source": "opencode-cache",
       "target": "/home/vscode/.cache/opencode",
       "type": "volume"
+    },
+    {
+      "source": "opencode-state",
+      "target": "/home/vscode/.local/state/opencode",
+      "type": "volume"
     }
   ],
   "containerEnv": {

src/opencode/install.sh

@@ -30,7 +30,7 @@ su - "$USERNAME" -c "curl -fsSL https://opencode.ai/install | bash -s -- ${VERSI
 mkdir -p "$USER_HOME/.local/share/opencode"
 mkdir -p "$USER_HOME/.config/opencode"
 mkdir -p "$USER_HOME/.cache/opencode"
-mkdir -p "$USER_HOME/.local/state"
+mkdir -p "$USER_HOME/.local/state/opencode"
 
 chown -R "$USERNAME:$USERNAME" "$USER_HOME/.local/share/opencode"
 chown -R "$USERNAME:$USERNAME" "$USER_HOME/.config/opencode"