Fetch repositories with remote ID if possible (#1078)

Use IDs of the forge to fetch repositories instead of their names and owner names. This improves handling of renamed and transferred repos.

TODO

- [ ] try to support as many forges as possible
    - [x] Gogs (no API)
    - [ ] Bitbucket Server
    - [x] Coding (no API?)
- [x] update repo every time it is fetched or received from the forge
- [x] if repo remote IDs are not available, use owner / name to get it
- [x] handle redirections (redirect a renamed repo to its new path)
- [x] ~~pull all repos once during migration to update ID (?)~~ issue fixed by on-demand loading of remote IDs
- [x] handle redirections in web UI
- [ ] improve handling of hooks after a repo was renamed (currently it checks for a redirection to the repo)
- [x] tests
- [x] `UNIQUE` constraint for remote IDs after migration shouldn't work (all repos have an empty string as remote ID)

close #854
close #648 partial
close https://codeberg.org/Codeberg-CI/feedback/issues/46

Possible follow-up PRs
- apply the same scheme on everything fetched from the remote (currently only users)

Co-authored-by: 6543 <6543@obermui.de>

Makefile

@@ -57,8 +57,8 @@ vendor:
 	go mod tidy
 	go mod vendor
 
-format:
-	@gofmt -s -w ${GOFILES_NOVENDOR}
+format: install-tools
+	@gofumpt -extra -w ${GOFILES_NOVENDOR}
 
 .PHONY: docs
 docs:
@@ -140,6 +140,9 @@ install-tools:
 	fi ; \
 	hash lint > /dev/null 2>&1; if [ $$? -ne 0 ]; then \
 		go install github.com/rs/zerolog/cmd/lint@latest; \
+	fi ; \
+	hash gofumpt > /dev/null 2>&1; if [ $$? -ne 0 ]; then \
+		go install mvdan.cc/gofumpt@latest; \
 	fi
 
 cross-compile-server: