chore: repoint URLs at git.swaits.com and bump for release

Rewrites remaining github.com / git.sr.ht references to git.swaits.com,
translating GitHub URL shapes to Gitea's (/blob/<ref>/ -> /src/branch/<ref>/,
/tree/<tag> -> /src/tag/<tag>, /actions/workflows/X -> /actions?workflow=X,
/edit/ -> /_edit/).

Left pointing at GitHub on purpose: pull-request links (PRs were not migrated)
and GitHub-only surfaces Gitea lacks (security advisories, discussions).

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "vivaldi-nc"
-version = "0.6.12"
+version = "0.6.13"
 edition = "2021"
 authors = ["Stephen Waits <steve@waits.net>"]
 description = "Vivaldi network coordinates for fast, distributed latency estimates in multinode networks, with a clean and simple interface."
@@ -9,7 +9,7 @@ keywords = ["vivaldi", "network", "coordinates", "distributed", "p2p"]
 categories = ["algorithms", "network-programming"]
 documentation = "https://docs.rs/vivaldi-nc/"
 readme = "README.md"
-homepage = "https://github.com/swaits/vivaldi-nc"
+homepage = "https://git.swaits.com/swaits/vivaldi-nc"
 repository = "https://git.swaits.com/swaits/vivaldi-nc"
 exclude = ["examples/*"]
 rust-version = "1.65"

README.md

@@ -174,7 +174,7 @@ Adding some detail to these three fields:
 To run the example, first clone the repository locally:
 
 ```bash
-git clone https://git.sr.ht/~swaits/vivaldi-nc
+git clone https://git.swaits.com/swaits/vivaldi-nc
 ```
 
 Then `cd` into the local clone and run the example: