feat(progress): implement milestone submission and approval contract …

[Bosun-Josh121]

Summary

Closes #218

Implements the progress Soroban smart contract for milestone submission and approval by trusted validators, with automatic player progress tier transitions on approval.

Changes

shared/src/errors.rs

• Added AlreadyVerified = 6 (fills the gap between InvalidInput = 5 and InsufficientFee = 7)

progress/Cargo.toml

• Added register as a dev-dependency (required for cross-contract test setup, mirrors the pattern in connection)

progress/src/lib.rs

Full implementation replacing the prior stub:

Function	Description
initialize(admin, register_contract)	One-time setup; stores admin + register contract address
register_validator(validator_address)	Admin-only; adds validator to registry
revoke_validator(validator_address)	Admin-only; removes validator from registry
submit_milestone(validator, player_id, milestone_type, evidence_uri)	Validates caller is a registered validator, auto-increments milestone ID, stores MilestoneData, appends to player history, emits milestone_submitted
approve_milestone(validator, milestone_id)	Validates caller is a registered validator, guards against double-approval, maps milestone type to progress level, cross-calls register.update_progress_level, emits milestone_approved
get_milestones(player_id)	Read-only; returns full Vec<MilestoneData> from ledger storage

Progress Tier Transitions

Milestone Type	Level Set	Spec
"identity"	1	Level 0 → 1
"performance"	2	Level 1 → 2
(handled by connection.rs)	3	Level 2 → 3

Error Codes

Variant	Discriminant	Triggered When
NotFound	4	Caller is not a registered validator
InvalidInput	5	Milestone ID does not exist
AlreadyVerified	6	Milestone has already been approved
Unauthorized	9	Non-admin calls register_validator / revoke_validator

Cross-Contract Call

approve_milestone calls register.update_progress_level(player_id, level) via env.invoke_contract — same pattern used in connection.rs — to avoid pulling the register rlib into the progress WASM and causing duplicate symbol errors.

Tests

All 8 tests pass under cargo test -p progress --target x86_64-unknown-linux-gnu.

• Non-validator cannot call submit_milestone
• Registered validator can submit and approve a milestone
• Approving an already-approved milestone returns AlreadyVerified
• "identity" milestone sets player progress to level 1
• "performance" milestone sets player progress to level 2
• get_milestones returns full tamper-proof history
• Revoked validator cannot submit
• Double initialize fails