feat(03-06): add Salesforce, ServiceNow, SAP, Palantir Tier 9 providers

- Keyword-only detection; strong env var anchors
- Dual-located in providers/ and pkg/providers/definitions/

providers/palantir.yaml

@@ -0,0 +1,18 @@
+format_version: 1
+name: palantir
+display_name: Palantir AIP
+tier: 9
+last_verified: "2026-04-05"
+keywords:
+  - "palantir"
+  - "foundry"
+  - "PALANTIR_TOKEN"
+  - "FOUNDRY_TOKEN"
+  - "palantirfoundry.com"
+  - "aip-agents"
+verify:
+  method: GET
+  url: ""
+  headers: {}
+  valid_status: []
+  invalid_status: []