v1.12.1

Changelog

• ee68fa5: docs: repoint the conformance receipt at the v1.12.0 run (@blakebauman)
• bd54136: fix: bump Go to 1.26.6 for six standard-library advisories (#64) (@blakebauman)
• 5f41c8e: docs: split the configuration reference and changelog out of the README (#63) (@blakebauman)
• 0c2c37d: fix: stop health probes from tearing down caller-derived upstreams (#66) (@blakebauman)
• d5995e8: fix: give caller-derived upstreams their own session per principal (#68) (@blakebauman)
• 4560398: fix: bound the per-key fetch gates in UpstreamCredentials (#65) (@blakebauman)
• 30d25f6: docs: changelog the three caller-derived credential fixes (#69) (@blakebauman)
• c8ead1f: release: v1.12.1 — per-caller upstream sessions (@blakebauman)