Rebrand: Sentry -> Cairn OBS

Full rebrand across cosmetic branding, code identifiers, and
infrastructure/data-plane naming, using the supplied Cairn OBS logo
package. Cosmetic: favicon/logo swap (also closes a stale license-audit
finding -- the old favicon was SvelteKit's unreplaced scaffold logo),
new centered welcome landing page, larger/legible sidebar logo, page
titles, CLAUDE.md/README/docs prose.

Code identifiers: Go module path github.com/sentry/sentry ->
github.com/cairnobs/cairnobs across all 13 modules and ~91 files (protoc
regenerated); Rust crates sentry-agent/sentry-parser/sentry-search ->
cairnobs-*; CLI sentryctl -> cairnobsctl; Terraform provider fully
renamed (sentry_dashboard etc. -> cairnobs_dashboard, provider type,
env vars); every session/auth cookie name; agent config paths and
Windows service identity.

Deliberately preserved: the gRPC wire protocol's protobuf packages
(sentry.logs.v1, sentry.agent.v1) and their Go import directory
(proto/sentry/...) -- renaming the wire-level package would break every
currently-deployed agent binary (confirmed two real hosts, including
mail.inbuxa.com, are actively streaming through this exact contract)
until rebuilt and redeployed in lockstep with an ingest cutover. Only
the Go module path wrapping the generated code changes.

Infrastructure: every docker-compose container name (root and three
component-level compose files); the Helm chart (directory, Chart.yaml,
named-template helpers, all templates, values.yaml image repos);
Kubernetes Operator (CRD group sentry.io -> cairnobs.io, both CRD YAML
files, Go identifiers, RBAC markers); the coupled enterprise/tenantcrd
package. Caught and fixed real path-coupling bugs along the way: the
Helm chart's search/ingest volume mounts and the dev-only-credential
detection constant vs. docker-compose.yml's literal values had to move
together or a security warning would have silently stopped firing.

Data plane: Postgres database sentry_metadata -> cairnobs_metadata and
role sentry -> cairnobs; ClickHouse database sentry -> cairnobs; Kafka
topic sentry.logs.raw -> cairnobs.logs.raw and its consumer groups.
Source-level defaults, docker-compose.yml, and every migrate.sh/
provision script default updated together; already-applied migration
files left untouched per this repo's immutable-migration convention.

Verified at every layer: all 13 Go modules build/vet/test clean, both
Rust workspaces (agent, search) build/clippy/test clean, npm run check/
build clean, docker compose config validates on all four compose files.
Live-verified against a real docker stack multiple times through this
work, including a final fresh-volume run confirming the actual renamed
Postgres database/role, ClickHouse database, and Kafka topic all work
end to end with a real login and query, zero console errors.

enterprise/internal/saml/saml.go

@@ -1,7 +1,7 @@
 // Package saml wires crewjam/saml into a small SP (service provider)
 // client: build the login redirect, and validate/parse an incoming
 // assertion. Deliberately not using crewjam's samlsp.Middleware, which
-// owns its own session/cookie handling -- Sentry's session concept lives
+// owns its own session/cookie handling -- Cairn OBS's session concept lives
 // in internal/session, one layer up, so this package only does the SAML
 // protocol mechanics (XML signing/parsing), per the explicit instruction
 // not to hand-roll that crypto.
@@ -23,7 +23,7 @@ import (
 )
 
 type Config struct {
-	// EntityID identifies Sentry to the IdP, conventionally Sentry's own
+	// EntityID identifies Cairn OBS to the IdP, conventionally Cairn OBS's own
 	// metadata URL.
 	EntityID string
 	// ACSURL is where the IdP redirects the browser back to with the
@@ -109,7 +109,7 @@ func (s *ServiceProvider) LoginURL(relayState string) (redirectURL, requestID st
 	return redirect.String(), req.ID, nil
 }
 
-// Claims is the subset of an assertion Sentry uses -- same "extend
+// Claims is the subset of an assertion Cairn OBS uses -- same "extend
 // deliberately" reasoning as oidc.Claims.
 type Claims struct {
 	NameID string
@@ -117,7 +117,7 @@ type Claims struct {
 }
 
 // ParseResponse validates an incoming SAML response (signature, issuer,
-// audience, timing) and extracts the fields Sentry cares about. This is
+// audience, timing) and extracts the fields Cairn OBS cares about. This is
 // the step that actually establishes trust -- crewjam/saml's
 // ParseResponse does the XML signature verification, not this package.
 func (s *ServiceProvider) ParseResponse(r *http.Request, possibleRequestIDs []string) (*Claims, error) {
@@ -186,7 +186,7 @@ func selfSignedCert() (*tls.Certificate, error) {
 	}
 	template := x509.Certificate{
 		SerialNumber:          serial,
-		Subject:               pkix.Name{CommonName: "sentry-saml-sp-dev"},
+		Subject:               pkix.Name{CommonName: "cairnobs-saml-sp-dev"},
 		NotBefore:             time.Now().Add(-time.Hour),
 		NotAfter:              time.Now().Add(24 * time.Hour * 365),
 		KeyUsage:              x509.KeyUsageDigitalSignature | x509.KeyUsageKeyEncipherment,