Enhance dynconfig with local fallback, static addresses, and health checks (#1944)

feat(dynconfig): support local file fallback when manager not configured


Make manager config optional; use local file fallback when absent
Extract remote (manager) logic into remote.rs and add new
local.rs for file-based dynconfig with DNS scheduler discovery
Introduce Source enum to dispatch between remote and local refresh
Local source reads dynconfig.yaml from config dir, resolves
schedulers via DNS, and controls its own refresh interval
Add serde_yaml and humantime-serde dependencies for local config

Signed-off-by: Gaius gaius.qi@gmail.com

feat(dynconfig): add static scheduler addrs and default config gen


Add addrs field to SchedulerConfig for static IP list; takes
precedence over DNS-based addr when non-empty
Add parse_schedulers to resolve static addresses, deduplicating and
sorting for stable selection
Add generate_default_if_absent to write default config file if none
exists; called during initialization
Derive Serialize on config types to support YAML generation
Add tests covering static addrs, precedence, invalid input, and
default file generation

Signed-off-by: Gaius gaius.qi@gmail.com

refactor(dynconfig): rename Source to Backend, expose path as CLI arg


Rename Source enum to Backend and update all references/comments
Move default helpers (refresh_interval, scheduler_addr) to
dragonfly_client_config::dfdaemon for broader reuse
Add --dynconfig CLI arg (with env var) instead of deriving path
from config file location
Rename generate_default_if_absent to generate_default and
update test names for clarity
Remove DEFAULT_DYNCONFIG_FILENAME constant; add
default_dfdaemon_dynconfig_path() to config crate

Signed-off-by: Gaius gaius.qi@gmail.com

fix(dynconfig): change scheduler addrs field from Vec to Option


Change addrs field type from Vec<String> to Option<Vec<String>>
Default value is now None instead of empty Vec
Update match logic to fall back to DNS resolution when addrs is
None or empty
Update serde skip condition accordingly

Signed-off-by: Gaius gaius.qi@gmail.com

refactor(dynconfig): rename LocalConfig/SchedulerConfig to Config/`Scheduler


Rename LocalConfig → Config and SchedulerConfig → Scheduler
in local.rs
Alias Scheduler from manager API as ManagerScheduler to avoid
name clash
Update all internal usages, defaults, and test assertions accordingly

Signed-off-by: Gaius gaius.qi@gmail.com

refactor(dynconfig): move empty addr check to caller, add skip_serializing_if


Move empty addr check from resolve_schedulers to its call site
Add skip_serializing_if = "Option::is_none" to skip_verify and
ca fields
Clarify comments for client_config and seed_client_config fields
Minor formatting fixes (blank lines)

Signed-off-by: Gaius gaius.qi@gmail.com

feat(dynconfig): add scheduler health check filtering in local backend


Perform health checks on schedulers in local backend, filtering out
unhealthy ones
Return error if no healthy schedulers are available after filtering
Increase default local dynconfig refresh interval from 5s to 60s
Pass DfdaemonConfig to Local to access TLS settings for health
checks
Add tests for unhealthy scheduler filtering and failure cases
Refactor Dynconfig::new to extract backend() helper; switch to
interval-based refresh loop

Signed-off-by: Gaius gaius.qi@gmail.com

refactor(grpc): pass Manager reference directly to ManagerClient::new


Replace Arc<Config> with &Manager in ManagerClient::new
signature
Remove indirection through config.manager option unwrap
Call config.load_client_tls_config directly on the Manager ref
Update call site and tests accordingly

Signed-off-by: Gaius gaius.qi@gmail.com

style: use inline format args in dynconfig local tests

Replace positional {} placeholders with inline variable references in
format! calls, improving readability and reducing argument lists.
Signed-off-by: Gaius gaius.qi@gmail.com

Signed-off-by: Gaius gaius.qi@gmail.com