feat(config): unify config resolution with Settings fallback (Phase 2, #1119)

[reidliu41]

Summary

Five config modules ignored their Settings structs, meaning values
saved via config set or the setup wizard had no effect at runtime.
This also closes the Phase 1 gap where auto-generated gateway tokens
were lost on restart.

• Wire WasmConfig::resolve() to read WasmSettings (7 fields)
• Wire SandboxModeConfig::resolve() to read SandboxSettings (8 fields)
• Wire BuilderModeConfig::resolve() to read BuilderSettings (5 fields)
• Wire resolve_safety_config() to read SafetySettings (2 fields)
• Wire ClaudeCodeConfig::resolve() to read sandbox.claude_code_enabled, fixing a bug where the setup wizard's choice was silently ignored
• Preserve ClaudeCodeConfig::from_env() for worker containers (no DB)
• Persist auto-generated GATEWAY_AUTH_TOKEN to "default" namespace so it survives restarts without requiring an env var
• Add ENV_MUTEX to all new env-mutating tests for parallel safety

Change Type

• Bug fix
• New feature
• Refactor
• Documentation
• CI/Infrastructure
• Security
• Dependencies

Linked Issue

Part of #1119 (Phase 2)

Validation

• cargo fmt
• cargo clippy --all --benches --tests --examples --all-features
• Relevant tests pass:
• Manual testing:

Security Impact

None

Database Impact

None

Blast Radius

Rollback Plan

---

Review track:

[gemini-code-assist]

Summary of Changes

Hello, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request significantly refactors the configuration resolution mechanism across several core modules, ensuring that settings persisted via the 'config set' command or the setup wizard are correctly applied at runtime. It addresses a critical gap where previously, certain configuration values and auto-generated gateway tokens were not consistently loaded after application restarts. The changes unify the configuration flow, prioritizing environment variables while falling back to stored settings, and include new tests to validate this behavior.

Highlights

• Unified Configuration Resolution: Updated several config modules (WasmConfig, SandboxModeConfig, BuilderModeConfig, SafetyConfig, ClaudeCodeConfig) to properly read values from Settings structs, ensuring 'config set' and setup wizard changes are respected.
• Gateway Token Persistence: Resolved an issue where auto-generated gateway tokens were lost on restart by persisting them to the 'default' settings namespace.
• Claude Code Config Fix: Fixed a bug where the setup wizard's choice for 'claude_code_enabled' was ignored.
• Environment Variable Resolution Refinement: Refactored ClaudeCodeConfig::from_env() to use a new resolve_env_only() method, preserving its functionality for worker containers without database access.
• Test Safety Improvement: Introduced ENV_MUTEX for new environment-mutating tests to ensure parallel safety.

Changelog

• src/config/builder.rs
  • Modified BuilderModeConfig::resolve to accept settings and use settings.builder as a fallback for configuration values.
  • Added unit tests to verify that resolve correctly falls back to Settings values and that environment variables override Settings.
• src/config/mod.rs
  • Updated the main Config::resolve function to pass the settings object to the resolve methods of safety, wasm, builder, sandbox, and claude_code configurations.
• src/config/safety.rs
  • Modified resolve_safety_config to accept settings and use settings.safety as a fallback for max_output_length and injection_check_enabled.
  • Added unit tests to confirm resolve_safety_config's fallback and override behavior.
• src/config/sandbox.rs
  • Modified SandboxModeConfig::resolve to accept settings and use settings.sandbox for fallback values for most fields, including extra_allowed_domains.
  • Renamed ClaudeCodeConfig::resolve to resolve_env_only and created a new resolve method that incorporates settings.sandbox.claude_code_enabled as a fallback.
  • Added unit tests for SandboxModeConfig and ClaudeCodeConfig to validate settings fallback and environment variable overrides.
• src/config/wasm.rs
  • Modified WasmConfig::resolve to accept settings and use settings.wasm as a fallback for configuration values like enabled, tools_dir, default_memory_limit, default_timeout_secs, default_fuel_limit, cache_compiled, and cache_dir.
  • Added unit tests to verify WasmConfig::resolve's fallback and override logic.
• src/main.rs
  • Implemented logic to persist auto-generated GATEWAY_AUTH_TOKEN to the 'default' settings namespace in the database, ensuring its survival across restarts.

Activity

• No specific activity (comments, reviews, progress updates) has been recorded for this pull request yet.

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[gemini-code-assist]

Code Review

This pull request is a solid improvement that unifies configuration resolution for several modules (builder, safety, sandbox, wasm, claude_code) to fall back to Settings values from the database. This ensures that settings configured via config set or the setup wizard are correctly applied at runtime. The addition of tests for this new fallback logic is excellent. Furthermore, the change to persist the auto-generated gateway auth token fixes an important bug where the token was lost on restart. I have one minor suggestion to simplify the code.

[gemini-code-assist]

The logic inside unwrap_or_else can be simplified. Cloning an empty Vec is efficient, so the if/else block is unnecessary and can be reduced to a single expression.

            .unwrap_or_else(|| ss.extra_allowed_domains.clone());

[zmanian]

Review: APPROVE

Well-structured, low-risk PR that methodically wires 5 config modules to read from persisted Settings as fallback when env vars aren't set. Previously, values set via config set or the setup wizard were silently ignored at runtime.

Modules wired: WasmConfig (7 fields), SandboxModeConfig (8 fields), BuilderModeConfig (5 fields), safety config (2 fields), ClaudeCodeConfig (1 field).

Architecture: Consistent pattern across all modules -- priority chain is env var > settings > hardcoded default. Matches how already-wired modules (AgentConfig, HeartbeatConfig, etc.) work.

Notable decisions:

• ClaudeCodeConfig cleanly split into resolve(settings) and resolve_env_only() for worker containers without DB access
• Gateway auth token persisted via db.set_setting() to survive restarts
• Fully backward compatible -- env vars still take priority, default values match previous hardcoded defaults

Minor suggestions (non-blocking):

1. Simplify extra_allowed_domains fallback -- the if is_empty() check is unnecessary:

// Before (unnecessary conditional)
.unwrap_or_else(|| {
    if ss.extra_allowed_domains.is_empty() {
        Vec::new()
    } else {
        ss.extra_allowed_domains.clone()
    }
})
// After
.unwrap_or_else(|| ss.extra_allowed_domains.clone())

2. Add a test for the extra_allowed_domains settings fallback path.
3. Add a test for ClaudeCodeConfig::from_env() container path to guard against regressions.

CI all green. Safe to merge.