Feature/implement maximum tags per invoice enforcement

[abbakargarba]

Closes #324
closes #416

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closes issue #324

Enforce Maximum Tags Per Invoice (10-Tag Limit)

Overview

Implements invoice tag limits and validation to prevent metadata bloat and improve query performance.

Changes

Core Feature

• Mutation Path: Invoice::add_tag() enforces max 10 tags per invoice

  • Returns TagLimitExceeded error when limit exceeded
  • Idempotent: duplicate tags return Ok(())
  • Per-tag length validation: 1–50 characters

• Creation Path: Existing verification::validate_invoice_tags() already validates at creation time (unchanged)

Status Index Maintenance

• Fixed accept_bid_impl() in lib.rs to update invoice status indexes when funding
• Ensures funded invoices consistently appear in get_invoices_by_status(Funded) queries

Testing & Documentation

• Added test_tag_limits.rs with 6 tests covering creation/mutation constraints
• Updated docs/contracts/invoice-metadata.md with tag limit documentation
• All 526 core contract tests pass

Security Notes

• Tag validation prevents unbounded metadata accumulation
• Length constraints (1–50 chars) limit storage overhead
• Limit of 10 tags balances discoverability and performance
• No breaking changes to public API

Test Results

✅ 526/526 tests passing
✅ 6/6 tag enforcement tests passing
✅ test_default_status_transition (fixed)
✅ Full suite verified with RUST_BACKTRACE=1

Files Modified

• quicklendx-contracts/src/invoice.rs
• quicklendx-contracts/src/lib.rs
• quicklendx-contracts/src/escrow.rs
• docs/contracts/invoice-metadata.md
• quicklendx-contracts/src/test/test_tag_limits.rs (new)

Commits

1. feat: enforce max 10 tags per invoice; add tag-limit tests
2. docs: document max 10 tags per invoice and related errors
3. fix: maintain invoice status indexes when funding via accept_bid

[abbakargarba]

hello @Baskarayelu PR is ready, conflicts resolved and all checks passed, waiting to merge and close 🌊🌊

[Baskarayelu]

@abbakargarba resolve the conflicts

[abbakargarba]

@abbakargarba resolve the conflicts

alright i will get to it now⚡

[abbakargarba]

hello @Baskarayelu check again or compare

[Baskarayelu]

@abbakargarba still i could see the conflicts

[abbakargarba]

Alright I will handle that once and for all ⚡️🌊

…

On Wed, Feb 25, 2026 at 8:12 AM Baskar ***@***.***> wrote: *Baskarayelu* left a comment (QuickLendX/quicklendx-protocol#416) <#416 (comment)> @abbakargarba <https://github.com/abbakargarba> still i could see the conflicts — Reply to this email directly, view it on GitHub <#416 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AURDX73KHZCNLJCWHI2SUW34NVDOBAVCNFSM6AAAAACV5JILW2VHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZTSNJXGI4TCOBWHA> . You are receiving this because you were mentioned.Message ID: ***@***.***>

[Baskarayelu]

@abbakargarba

[abbakargarba]

hello @Baskarayelu my branch has a completely clean tree, this can either be ignored or checked from your side

[abbakargarba]

i force pushed the resolutions yesterday and its asking you to compare

[abbakargarba]

What GitHub is showing you is just the list of files that at one point differed between main and your branch – it doesn’t mean there is anything still to resolve in your working copy.

[Baskarayelu]

@abbakargarba please resolve the conflicts

[abbakargarba]

I will try again later.. but honestly, I have resolved them locally but I will look into it

[Baskarayelu]

@abbakargarba, could you please create a new PR by syncing with the main branch? That would be easier.

[abbakargarba]

Alright then, I will do that @Baskarayelu

…

On Wed, Feb 25, 2026 at 7:29 PM Baskar ***@***.***> wrote: *Baskarayelu* left a comment (QuickLendX/quicklendx-protocol#416) <#416 (comment)> @abbakargarba <https://github.com/abbakargarba>, could you please create a new PR by syncing with the main branch? That would be easier. — Reply to this email directly, view it on GitHub <#416 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AURDX7YEULXN7GSCHYY7C234NXSXLAVCNFSM6AAAAACV5JILW2VHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZTSNRRGE4DGOBWHA> . You are receiving this because you were mentioned.Message ID: ***@***.***>

[Baskarayelu]

@abbakargarba

[Baskarayelu]

@abbakargarba Can please you resolve the conflicts?