feat: bring repo up to REPO_POLICIES standards

- Create cmd/webhooker/main.go with fx dependency injection wiring
- Add REPO_POLICIES.md, .editorconfig, .dockerignore
- Add .gitea/workflows/check.yml for CI (docker build on push)
- Rewrite Makefile with all required targets (test, lint, fmt, fmt-check,
  check, build, hooks, docker, clean, dev, run, deps)
- Rewrite Dockerfile with sha256-pinned base images, golangci-lint
  installed from verified release archive, make check as build step
- Fix README.md: add required sections (description, getting started,
  rationale, design, TODO, license, author)
- Integrate TODO.md content into README.md and remove TODO.md
- Move config.yaml to configs/config.yaml.example
- Fix .gitignore pattern for webhooker binary
- Fix static/static.go embed directive (remove empty vendor dir)
- Fix database test to use in-memory config (no filesystem dependency)

closes #1
closes #2

go.mod

@@ -15,7 +15,7 @@ require (
 	github.com/joho/godotenv v1.5.1
 	github.com/prometheus/client_golang v1.18.0
 	github.com/slok/go-http-metrics v0.11.0
-	github.com/spf13/viper v1.18.2
+	github.com/spf13/afero v1.14.0
 	github.com/stretchr/testify v1.8.4
 	go.uber.org/fx v1.20.1
 	golang.org/x/crypto v0.38.0
@@ -34,42 +34,30 @@ require (
 	github.com/cespare/xxhash/v2 v2.2.0 // indirect
 	github.com/davecgh/go-spew v1.1.2-0.20180830191138-d8f796af33cc // indirect
 	github.com/dustin/go-humanize v1.0.1 // indirect
-	github.com/fsnotify/fsnotify v1.7.0 // indirect
 	github.com/golang/groupcache v0.0.0-20210331224755-41bb18bfe9da // indirect
 	github.com/golang/protobuf v1.5.3 // indirect
 	github.com/google/s2a-go v0.1.7 // indirect
 	github.com/googleapis/enterprise-certificate-proxy v0.3.2 // indirect
 	github.com/googleapis/gax-go/v2 v2.12.0 // indirect
 	github.com/gorilla/securecookie v1.1.2 // indirect
-	github.com/hashicorp/hcl v1.0.0 // indirect
 	github.com/jinzhu/inflection v1.0.0 // indirect
 	github.com/jinzhu/now v1.1.5 // indirect
 	github.com/jmespath/go-jmespath v0.4.0 // indirect
 	github.com/kballard/go-shellquote v0.0.0-20180428030007-95032a82bc51 // indirect
-	github.com/magiconair/properties v1.8.7 // indirect
+	github.com/kr/text v0.2.0 // indirect
 	github.com/mattn/go-isatty v0.0.20 // indirect
 	github.com/mattn/go-sqlite3 v1.14.17 // indirect
 	github.com/matttproud/golang_protobuf_extensions/v2 v2.0.0 // indirect
-	github.com/mitchellh/mapstructure v1.5.0 // indirect
-	github.com/pelletier/go-toml/v2 v2.1.0 // indirect
 	github.com/pmezard/go-difflib v1.0.1-0.20181226105442-5d4384ee4fb2 // indirect
 	github.com/prometheus/client_model v0.5.0 // indirect
 	github.com/prometheus/common v0.45.0 // indirect
 	github.com/prometheus/procfs v0.12.0 // indirect
 	github.com/remyoudompheng/bigfft v0.0.0-20230129092748-24d4a6f8daec // indirect
-	github.com/sagikazarmark/locafero v0.4.0 // indirect
-	github.com/sagikazarmark/slog-shim v0.1.0 // indirect
-	github.com/sourcegraph/conc v0.3.0 // indirect
-	github.com/spf13/afero v1.14.0 // indirect
-	github.com/spf13/cast v1.6.0 // indirect
-	github.com/spf13/pflag v1.0.5 // indirect
-	github.com/subosito/gotenv v1.6.0 // indirect
 	go.opencensus.io v0.24.0 // indirect
 	go.uber.org/atomic v1.9.0 // indirect
 	go.uber.org/dig v1.17.0 // indirect
 	go.uber.org/multierr v1.9.0 // indirect
 	go.uber.org/zap v1.23.0 // indirect
-	golang.org/x/exp v0.0.0-20230905200255-921286631fa9 // indirect
 	golang.org/x/mod v0.17.0 // indirect
 	golang.org/x/net v0.25.0 // indirect
 	golang.org/x/oauth2 v0.15.0 // indirect
@@ -85,7 +73,6 @@ require (
 	google.golang.org/genproto/googleapis/rpc v0.0.0-20231120223509-83a465c0220f // indirect
 	google.golang.org/grpc v1.59.0 // indirect
 	google.golang.org/protobuf v1.31.0 // indirect
-	gopkg.in/ini.v1 v1.67.0 // indirect
 	gopkg.in/yaml.v3 v3.0.1 // indirect
 	lukechampine.com/uint128 v1.2.0 // indirect
 	modernc.org/cc/v3 v3.40.0 // indirect