SI-22: Extract torrust-located-error to a standalone repository

[josecelano]

Goal

Move the torrust-located-error crate out of the torrust-tracker workspace into its own standalone repository so that it can be maintained, versioned, and published independently of the tracker.

Background

The torrust-located-error package provides an error decorator that attaches source-location information to errors — a generic debugging utility with no tracker-specific logic. Its only runtime dependency is tracing, a general-purpose structured logging crate. The crate was renamed from torrust-tracker-located-error to torrust-located-error by SI-10 (#1823) which was completed in May 2026. The crate has zero workspace-path dependencies — its only runtime dep (tracing) is an external published crate. Extraction is therefore unblocked. The crate under its new name (torrust-located-error) is not yet published on crates.io. The old name (torrust-tracker-located-error v3.0.0) is published. Publishing torrust-located-error from the standalone repository is part of this issue's scope. This issue is a subissue of EPIC #1669 (Overhaul: Packages).

Scope

In Scope

• Create a new standalone repository torrust/torrust-located-error in the Torrust GitHub organisation.
• Move packages/located-error/ to the new repository, preserving git history (using git filter-repo).
• Make Cargo.toml self-contained (remove workspace inheritance).
• Verify the standalone repository builds and tests pass independently.
• Set up CI in the new repository (mirror the relevant CI workflows from the tracker repo).
• Publish torrust-located-error on crates.io from the new standalone repository.
• Update all 5 workspace consumers (see list below) to reference torrust-located-error as a crates.io version dependency instead of a path dependency.
• Remove the path-based dep registration from root Cargo.toml if present.
• Remove packages/located-error from the workspace if listed.
• Delete the packages/located-error/ directory from the tracker repository.
• Update prose references in packages/AGENTS.md, AGENTS.md, and docs/packages.md (move torrust-located-error to the "Extracted" section).
• Yank the old torrust-tracker-located-error crate on crates.io after workspace consumers have been migrated.

Out of Scope

• Changes to the crate's API or behaviour.
• Updating downstream repositories outside the Torrust organisation.

Workspace consumers to migrate

The following 5 files must have their torrust-located-error dep changed from a path dep to a crates.io version dep:

• packages/configuration/Cargo.toml
• packages/http-protocol/Cargo.toml
• packages/axum-server/Cargo.toml
• packages/tracker-core/Cargo.toml
• packages/tracker-client/Cargo.toml

Implementation Plan

Status values: TODO, IN_PROGRESS, BLOCKED, DONE.

ID	Status	Task	Notes / Expected Output
T1	DONE	Verify crate has no workspace path dependencies	packages/located-error/Cargo.toml lists only external crates (tracing), plus thiserror as dev-dep
T2	DONE	Create standalone repository torrust/torrust-located-error	Repo created at https://github.com/torrust/torrust-located-error - initialised with no commits on main
T3	TODO	Move packages/located-error/ to the new repository (preserving git history)	New repo contains full history for packages/located-error/
T4	TODO	Make Cargo.toml self-contained (remove workspace inheritance; pin explicit values)	All fields explicit; no workspace = true entries
T5	TODO	Verify standalone repository: cargo build and cargo test pass with no path deps	Clean build and tests pass; no path deps remain
T6	TODO	Set up CI in the new repository	CI workflow with linter all + cargo test
T7	TODO	Publish torrust-located-error on crates.io from the standalone repository	Published v0.1.0 (or appropriate initial version); crates.io page exists
T8	TODO	Update all 5 workspace consumers (see list above): path dep -> crates.io version dep	torrust-located-error = "0.1.0" in all 5 files; no path deps remain
T9	TODO	Remove packages/located-error entry from workspace if listed	Verify root Cargo.toml [workspace] members list; remove if present
T10	TODO	Delete packages/located-error/ directory from the tracker repository	Directory removed via git rm -r
T11	TODO	Update packages/AGENTS.md, AGENTS.md, docs/packages.md	torrust-located-error moved to an "Extracted packages" section
T12	TODO	Yank old torrust-tracker-located-error from crates.io (optional, after downstream migrated)	cargo yank torrust-tracker-located-error@3.0.0
T13	TODO	Run cargo build --workspace and cargo test --workspace	Clean build and all tests pass
T14	TODO	Run linter all	Exit code 0
T15	TODO	Update EPIC #1669 tables	Package inventory and desired state tables updated; subissue row set to DONE

Verification Plan

Automatic Checks

• cargo build --workspace
• cargo test --doc --workspace
• cargo test --tests --workspace --all-targets --all-features
• linter all
• cargo machete (no unused dependencies)

Manual Verification Scenarios

ID	Scenario	Steps	Expected Result
M1	No path dep on torrust-located-error remains in workspace	grep -r "path.*packages/located-error" . --include="*.toml"	Zero matches
M2	packages/located-error/ directory is gone	ls packages/located-error	No such file or directory
M3	Standalone repo builds and tests pass independently	In new repo: cargo build && cargo test --workspace	Clean build; all tests pass
M4	New crate visible on crates.io	Visit https://crates.io/crates/torrust-located-error	Crate page exists
M5	torrust-located-error CI green in new repository	Check GitHub Actions on torrust/torrust-located-error	All workflows green