fix: Fix data and target availability for daemon mode

[keelerm84]

Note

Adjust availability calculations in FDv1/FDv2 and add tests for offline, LDD, data-source, and store-initialization states.

• Core datasystem logic:
  • FDv1 (ldclient/impl/datasystem/fdv1.py):
    • Update data_availability to return CACHED in LDD mode only when the store is initialized; otherwise DEFAULTS.
    • Update target_availability to return CACHED in LDD mode; DEFAULTS when offline; otherwise REFRESHED.
  • FDv2 (ldclient/impl/datasystem/fdv2.py):
    • Use config.offline directly in start() to disable the system.
    • Refine data_availability: REFRESHED when selector is defined; CACHED when store initialized; else DEFAULTS.
    • Refine target_availability: DEFAULTS when offline or no data sources and no store; REFRESHED when configured with data sources; otherwise CACHED.
• Tests:
  • Add test_fdv1_availability.py covering offline, LDD (initialized/uninitialized), and normal mode scenarios.
  • Expand test_fdv2_datasystem.py with availability cases for offline, with/without data sources, and read-only/read-write store (initialized/uninitialized).

^{Written by Cursor Bugbot for commit 1c998cd. This will update automatically on new commits. Configure here.}

[cursor]

Bug: Missing offline check in FDv2 data_availability property

The data_availability property in FDv2 is missing an offline check, unlike target_availability which explicitly checks self._config.offline and returns DEFAULTS. In FDv1, both properties check for offline mode first. Without this check, if the store happens to be initialized while in offline mode, data_availability would return CACHED instead of DEFAULTS, creating inconsistent behavior between the two availability properties and between FDv1 and FDv2.