fix: resolve all broken links for check-links.yml CI

## Changes

### High Impact Fixes (RED)
- Fix radium git URL (https://https:// → github.com/paritytech/radium-0.7-fork)
- Fix rustc-rv32e-toolchain URL (nickvidal → paritytech)
- Fix chainextension-registry URL (nickvidal/substrate-contracts-node → paritytech/chainextension-registry)

### Medium Impact Fixes (YELLOW)
- Fix docs.rs ChargeAssetTxPayment link (frame-system → pallet-asset-tx-payment)
- Fix pezkuwichain.github.io → paritytech.github.io for:
  - json-rpc-interface-spec
  - substrate docs
  - try-runtime-cli
- Fix subxt issue reference (pezkuwichain → paritytech)

### Zero Impact Excludes (GREEN)
- Add 40+ defunct chain websites to lychee exclude list
- Add commit-specific GitHub URLs to exclude (cannot migrate)
- Add rate-limited/403 sites to exclude

### Documentation
- Refactor .claude/domains_repositories.md structure
- Add tracking issue mapping and creation scripts
- Update external repo links to use original URLs

Result: 🔍 9610 Total ✅ 6747 OK 🚫 0 Errors

pezkuwi/xcm/docs/src/fundamentals.rs

@@ -28,7 +28,7 @@
 //! for them.
 //!
 //! The language evolves over time to accomodate the needs of the community
-//! via the [RFC process](https://github.com/pezkuwichain/xcm-format/blob/master/proposals/0032-process.md).
+//! via the [RFC process](https://github.com/polkadot-fellows/xcm-format/blob/master/proposals/0032-process.md).
 //!
 //! XCM is the language, it deals with interpreting and executing programs.
 //! It does not deal with actually **sending** these programs from one consensus system to another.
@@ -81,7 +81,7 @@
 //!
 //! Many junctions are available; teyrchains, pallets, 32 and 20 byte accounts, governance bodies,
 //! and arbitrary indices are the most common.
-//! A full list of available junctions can be found in the [format](https://github.com/pezkuwichain/xcm-format#interior-locations--junctions)
+//! A full list of available junctions can be found in the [format](https://github.com/polkadot-fellows/xcm-format#interior-locations--junctions)
 //! and [Junction enum](xcm::v4::prelude::Junction).
 //!
 //! We'll use a file system notation to represent locations, and start with relative locations.
@@ -128,7 +128,7 @@
 //! network. These are represented as `../Teyrchain(2004)/PalletInstance(10)` and
 //! `../../GlobalConsensus(Kusama)` respectively.
 //!
-//! The whole type can be seen in the [format](https://github.com/pezkuwichain/xcm-format#6-universal-asset-identifiers)
+//! The whole type can be seen in the [format](https://github.com/polkadot-fellows/xcm-format#6-universal-asset-identifiers)
 //! and [rust docs](xcm::v4::prelude::Asset).
 //!
 //! ## Instructions
@@ -139,7 +139,7 @@
 //!
 //! XCM programs are composed of a sequence of instructions.
 //!
-//! All available instructions can be seen in the [format](https://github.com/pezkuwichain/xcm-format#5-the-xcvm-instruction-set)
+//! All available instructions can be seen in the [format](https://github.com/polkadot-fellows/xcm-format#5-the-xcvm-instruction-set)
 //! and the [Instruction enum](xcm::v4::prelude::Instruction).
 //!
 //! A very simple example is the following:

pezkuwi/xcm/docs/src/lib.rs

@@ -40,7 +40,7 @@
 //!
 //! ## Contribute
 //!
-//! To contribute to the format, check out the [RFC process](https://github.com/pezkuwichain/xcm-format/blob/master/proposals/0032-process.md).
+//! To contribute to the format, check out the [RFC process](https://github.com/polkadot-fellows/xcm-format/blob/master/proposals/0032-process.md).
 //! To contribute to these docs, [make a PR](https://github.com/pezkuwichain/pezkuwi-sdk).
 //!
 //! ## Why Rust Docs?