feat: implement retry policy for jobs

[niteshpurohit]

• Introduced a new Karya::RetryPolicy class to manage retry and backoff behavior for jobs.
• Added configuration options for maximum attempts, base delay, multiplier, and optional maximum delay.
• Integrated retry policy into the worker configuration, allowing per-job overrides.
• Updated job attributes to include retry policy and next retry timestamp.
• Enhanced worker behavior to handle retry logic, transitioning jobs to a retry_pending state when necessary.
• Implemented tests to validate retry policy functionality and integration with job processing.
• Updated documentation to reflect new retry policy features and usage.

closes: #40

[Copilot]

Pull request overview

Implements core retry/backoff support for Karya jobs by introducing an immutable Karya::RetryPolicy, persisting retry metadata on jobs (retry_policy, next_retry_at), and teaching the in-memory queue store + worker to transition failed executions into a retry_pending waiting state and lazily re-promote due retries back to queued.

Changes:

• Add Karya::RetryPolicy (validation, deterministic exponential backoff, optional max-delay clamp) plus RBS + unit tests.
• Extend Karya::Job/attributes with retry_policy and next_retry_at, including transition support and specs.
• Integrate retries into Worker and QueueStore::InMemory (new retry_pending workflow, due-retry promotion during maintenance) plus integration tests and docs updates.

Reviewed changes

Copilot reviewed 30 out of 30 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
docs/pages/runtime/job-model.md	Documents retry metadata and retry_pending lifecycle semantics in the job model.
docs/pages/reliability/retries.md	Describes implemented retry behavior vs deferred follow-on work.
core/karya/spec/karya/worker_spec.rb	Adds worker configuration validation and retry policy exposure coverage.
core/karya/spec/karya/worker_integration_spec.rb	Adds end-to-end retry behavior tests (worker default vs job override).
core/karya/spec/karya/retry_policy_spec.rb	New unit tests for retry policy validation and backoff math.
core/karya/spec/karya/queue_store/in_memory_state_helpers_spec.rb	Adds coverage for retry-pending state tracking behavior.
core/karya/spec/karya/queue_store/in_memory_execution_spec.rb	Adds execution failure → retry_pending behavior and promotion tests.
core/karya/spec/karya/job/attributes_spec.rb	Validates new job attributes (retry_policy, next_retry_at).
core/karya/spec/karya/job_spec.rb	Ensures job immutability and transitions preserve/override retry metadata.
core/karya/sig/karya/worker/configuration.rbs	Adds retry_policy to worker configuration typing.
core/karya/sig/karya/worker.rbs	Types worker retry_policy and updated failure path signature.
core/karya/sig/karya/retry_policy.rbs	New RBS for Karya::RetryPolicy and error type.
core/karya/sig/karya/queue_store/in_memory.rbs	Extends queue store typing for retry policy + retry_pending tracking.
core/karya/sig/karya/queue_store/base.rbs	Updates fail_execution signature to accept optional retry policy.
core/karya/sig/karya/job/attributes.rbs	Types new job attribute fields in the canonical hash.
core/karya/sig/karya/job.rbs	Types job retry_policy and next_retry_at plus transition signature changes.
core/karya/sig/karya.rbs	Adds retry_policy type alias and allows it in option/job attribute unions.
core/karya/lib/karya/worker/configuration.rb	Adds validated retry_policy support to worker configuration.
core/karya/lib/karya/worker.rb	Uses effective retry policy (job override > worker default) on failure.
core/karya/lib/karya/retry_policy.rb	Implements validated, immutable retry policy behavior.
core/karya/lib/karya/queue_store/in_memory/store_state.rb	Adds retry-pending job ID tracking in in-memory store state.
core/karya/lib/karya/queue_store/in_memory/retry_support.rb	Adds due-retry promotion and retry_pending transition helpers.
core/karya/lib/karya/queue_store/in_memory/reserve_selection_support.rb	Extracts reserve-selection logic into a support module.
core/karya/lib/karya/queue_store/in_memory/execution_recovery.rb	Extracts execution recovery into a dedicated class file.
core/karya/lib/karya/queue_store/in_memory.rb	Wires retry support into in-memory store failure and maintenance paths.
core/karya/lib/karya/queue_store/base.rb	Updates abstract fail_execution signature to accept retry policy.
core/karya/lib/karya/job/attributes.rb	Normalizes/validates new retry attributes for jobs.
core/karya/lib/karya/job.rb	Persists retry metadata in canonical job structs and transitions.
core/karya/lib/karya.rb	Requires karya/retry_policy.
core/karya/.reek.yml	Updates reek exclusions for new/expanded APIs and helpers.

[Copilot]

Pull request overview

Copilot reviewed 30 out of 30 changed files in this pull request and generated 2 comments.

[Copilot]

Pull request overview

Copilot reviewed 30 out of 30 changed files in this pull request and generated 1 comment.

[Copilot]

Pull request overview

Copilot reviewed 30 out of 30 changed files in this pull request and generated no new comments.