fix: resolve CI failures by pinning dependencies and formatting code

[Jeshua Ben Joseph (Theaxiom)]

• Pinned cryptographic dependency versions (e.g., hkdf = "=0.12.4") in the workspace Cargo.toml and explicitly inherited rand_core = "=0.6.4" to prevent trait bound mismatches and missing dependency errors causing the build to fail.
• Refactored shared/src/crypto.rs to adapt to rand crate downgrade by utilizing rand::thread_rng().fill_bytes() correctly instead of rand::rng().
• Fixed formatting issues in Python test files to comply with black lint checks.
• Updated pytest expectation in coordinator/tests/unit/application/test_security_ports.py to handle the new TypeError message string used in the environment for instantiating abstract classes.

[Copilot]

Pull request overview

This PR aims to get CI green again by pinning Rust/Python dependency versions, adapting crypto RNG usage to match the rand downgrade, and applying formatting/test expectation fixes across the coordinator and worker.

Changes:

• Pin Rust crypto-related crate versions in the workspace and adjust shared crypto RNG usage for compatibility.
• Refactor coordinator job completion APIs to pass a value object (JobCompletionParams) instead of many parameters, updating tests accordingly.
• Fix Python formatting/lint issues and update a couple of brittle test assertions to match environment error messages.

Reviewed changes

Copilot reviewed 21 out of 24 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
worker/src/main.rs	Runs Axum server in a spawned task and monitors it via tokio::select!.
shared/src/crypto.rs	Updates RNG usage for X25519 secret generation and nonce creation after rand changes.
coordinator/tests/unit/test_main_module.py	Black-compatible formatting for subprocess cwd arg.
coordinator/tests/unit/infrastructure/persistence/test_database.py	Black/quote formatting and minor whitespace cleanup.
coordinator/tests/unit/infrastructure/audit/test_logger.py	Adds unit tests for AuditService logging + DB write behavior.
coordinator/tests/unit/infrastructure/audit/init.py	Adds package marker for audit unit tests.
coordinator/tests/unit/application/test_security_ports.py	Relaxes abstract-class instantiation error message assertion.
coordinator/tests/unit/application/test_orchestration_services.py	Updates orchestration tests to use JobCompletionParams.
coordinator/tests/unit/application/test_inference_services.py	Black formatting adjustments in tests.
coordinator/tests/unit/application/test_accounting_services.py	Updates accounting tests to use JobCompletionParams.
coordinator/tests/test_rate_limit.py	Whitespace formatting cleanup.
coordinator/tests/test_multiplier.py	Removes unused import and applies Black formatting.
coordinator/tests/test_cors_security.py	Removes unused import and applies Black formatting.
coordinator/tests/test_cors.py	Adds spacing for Black formatting.
coordinator/requirements.txt	Bumps cryptography patch version.
coordinator/main.py	Minor formatting (blank line).
coordinator/interface/api/inference.py	Simplifies peer serialization by calling Node.to_dict().
coordinator/domain/inference/models.py	Adds Node.to_dict() and reuses it from to_json().
coordinator/domain/accounting/models.py	Introduces JobCompletionParams value object.
coordinator/benchmark_reputation.py	Black formatting for arithmetic spacing in f-string.
coordinator/application/orchestration_services.py	Changes complete_job signature to accept JobCompletionParams.
coordinator/application/accounting_services.py	Changes process_job_completion signature to accept JobCompletionParams.
Cargo.toml	Pins Rust crypto/rand dependency versions to resolve build mismatches.
Cargo.lock	Updates lockfile to reflect pinned dependency graph changes.

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[Copilot]

If the heartbeat task ever exits (it’s an infinite loop, so this would only happen on panic/cancellation), the branch just logs and then main continues to return Ok(()), stopping the worker. Treat unexpected heartbeat task termination as a fatal error (e.g., return an error and/or abort the proxy task) so the process doesn’t exit “successfully” on internal failure.

[Copilot]

generate_keypair is generating secret material via thread_rng() and then constructing StaticSecret from raw bytes. For cryptographic key material it’s safer to use an OS-backed CSPRNG (you already import OsRng) and prefer the library’s RNG-based constructor (e.g., StaticSecret::random_from_rng) to ensure any required clamping/conditioning is applied consistently.

[Jeshua Ben Joseph (Theaxiom)]

Copilot apply changes based on the comments in this thread and also resolve merge conflicts.

[Copilot]

Copilot apply changes based on the comments in this thread and also resolve merge conflicts.

Applied all review changes and resolved merge conflicts in commit 67cc2f5:

• shared/src/crypto.rs: Switched generate_keypair back to use rand_core::OsRng + StaticSecret::random_from_rng(OsRng) — OS-backed CSPRNG with the library's proper constructor.
• worker/src/main.rs: Heartbeat task termination is now fatal — returns Err(anyhow::anyhow!("heartbeat task ended unexpectedly")) instead of logging and silently continuing. Both select arms now propagate errors (the trailing unreachable Ok(()) was also removed).
• Merged origin/main to resolve conflicts in Cargo.toml, Cargo.lock, shared/src/crypto.rs, worker/src/main.rs, and two Python test files.