feat: verify context attestations via ES256/JWKS + rename client to appshell-crm

Proof #3 now supports the production asymmetric path, not just the dev shared secret.

- context-attestation.ts: PublicKeyResolverPort seam; verify() picks ES256 (JWKS by
  kid) when the client has a jwksUri, else HS256 (dev). signDevAttestationES256 helper.
- attestation-stores.ts: JwksPublicKeyResolver (jwks-rsa, one cached client per URI,
  refetch on rotation, fail-closed to NO_KEY).
- attestation.module.ts: inject the resolver into the verifier; dev-seed the client as
  clientType APPSHELL (it is the CRM browser-flow parent per the July-12 notes).
- rename the registered client crm-support-widget -> appshell-crm (the name reflects the
  attesting parent, not a widget).
- specs: ES256 (valid via JWKS, wrong key -> BAD_SIGNATURE, unknown kid -> NO_KEY, no
  resolver -> NO_KEY) + two stolen-token gate cases (wrong app binding -> APP_MISMATCH,
  wrong audience -> WRONG_AUDIENCE).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

pnpm-lock.yaml

@@ -370,6 +370,9 @@ importers:
       jsonwebtoken:
         specifier: ^9.0.3
         version: 9.0.3
+      jwks-rsa:
+        specifier: ^4.1.0
+        version: 4.1.0
       prisma:
         specifier: ^6.2.1
         version: 6.19.3(typescript@5.9.3)
@@ -2297,6 +2300,9 @@ packages:
     resolution: {integrity: sha512-AC/7JofJvZGrrneWNaEnJeOLUx+JlGt7tNa0wZiRPT4MY1wmfKjt2+6O2p2uz2+skll8OZZmJMNqeke7kKbNgQ==}
     hasBin: true
 
+  jose@6.2.3:
+    resolution: {integrity: sha512-YYVDInQKFJfR/xa3ojUTl8c2KoTwiL1R5Wg9YCydwH0x0B9grbzlg5HC7mMjCtUJjbQ/YnGEZIhI5tCgfTb4Hw==}
+
   joycon@3.1.1:
     resolution: {integrity: sha512-34wB/Y7MW7bzjKRjUKTa46I2Z7eV62Rkhva+KkopW7Qvv/OSWBqvkSY7vusOPrNuZcUG3tApvdVgNB8POj3SPw==}
     engines: {node: '>=10'}
@@ -2343,6 +2349,10 @@ packages:
   jwa@2.0.1:
     resolution: {integrity: sha512-hRF04fqJIP8Abbkq5NKGN0Bbr3JxlQ+qhZufXVr0DvujKy93ZCbXZMHDL4EOtodSbCWxOqR8MS1tXA5hwqCXDg==}
 
+  jwks-rsa@4.1.0:
+    resolution: {integrity: sha512-sbkByqyATKYJP5F4RXj03N5TUNC0QLTjCAZvwTzC4BwJZ8e0/cWxN8YROnyUth2g1/ONWi4eSFHeu6oYalrc3Q==}
+    engines: {node: ^20.19.0 || ^22.12.0 || >= 23.0.0}
+
   jws@4.0.1:
     resolution: {integrity: sha512-EKI/M/yqPncGUUh44xz0PxSidXFr/+r0pA70+gIYhjv+et7yxM+s29Y+VGDkovRofQem0fs7Uvf4+YmAdyRduA==}
 
@@ -2353,6 +2363,9 @@ packages:
     resolution: {integrity: sha512-/vlFKAoH5Cgt3Ie+JLhRbwOsCQePABiU3tJ1egGvyQ+33R/vcwM2Zl2QR/LzjsBeItPt3oSVXapn+m4nQDvpzw==}
     engines: {node: '>=14'}
 
+  limiter@1.1.5:
+    resolution: {integrity: sha512-FWWMIEOxz3GwUI4Ts/IvgVy6LPvoMPgjMdQ185nN6psJyBJ4yOpzqm695/h5umdLJg2vW3GR5iG11MAkR2AzJA==}
+
   lines-and-columns@1.2.4:
     resolution: {integrity: sha512-7ylylesZQ/PV29jhEDl3Ufjo6ZX7gCqJr5F7PKrqc93v7fzSymt1BpwEU8nAUXs8qzzvqhbjhK5QZg6Mt/HkBg==}
 
@@ -2368,6 +2381,9 @@ packages:
     resolution: {integrity: sha512-DFEqQ3ihfS9blba08cLfYf1NRAIEm+dDjic073DRDc3/JspI/8wYmtDsHwd3+4hwvdxSK7PGaElfTmm0awWJ4w==}
     engines: {node: '>=6.11.5'}
 
+  lodash.clonedeep@4.5.0:
+    resolution: {integrity: sha512-H5ZhCF25riFd9uB5UCkVKo61m3S/xZk1x4wA6yp/L3RFP6Z/eHH1ymQcGLo7J3GMPfm0V/7m1tryHuGVxpqEBQ==}
+
   lodash.includes@4.3.0:
     resolution: {integrity: sha512-W3Bx6mdkRTGtlJISOvVD/lbqjTlPPUDTMnlXZFnVwi9NKJ6tiAk6LVdlhZMm17VZisqhKcgzpO5Wz91PCt5b0w==}
 
@@ -2406,6 +2422,9 @@ packages:
   lru-cache@5.1.1:
     resolution: {integrity: sha512-KpNARQA3Iwv+jTA0utUVVbrh+Jlrr1Fv0e56GGzAFOXN7dk/FviaDW8LHmK52DlcH4WP2n6gI8vN1aesBFgo9w==}
 
+  lru-memoizer@3.0.0:
+    resolution: {integrity: sha512-m83w/cYXLdUIboKSPxzPAGfYnk+vqeDYXuoSrQRw1q+yVEd8IXhvMufN8Q5TIPe7e2jyX4SRNrDJI2Skw1yznQ==}
+
   magic-string@0.30.17:
     resolution: {integrity: sha512-sNPKHvyjVf7gyjwS4xGTaW/mCnF8wnjtifKBEhxfZ7E/S8tQ0rssrwGNn6q8JH/ohItJfSQp9mBtQYuTlH5QnA==}
 
@@ -5066,6 +5085,8 @@ snapshots:
 
   jiti@2.7.0: {}
 
+  jose@6.2.3: {}
+
   joycon@3.1.1: {}
 
   js-tokens@4.0.0: {}
@@ -5113,6 +5134,17 @@ snapshots:
       ecdsa-sig-formatter: 1.0.11
       safe-buffer: 5.2.1
 
+  jwks-rsa@4.1.0:
+    dependencies:
+      '@types/jsonwebtoken': 9.0.10
+      debug: 4.4.3
+      jose: 6.2.3
+      limiter: 1.1.5
+      lru-cache: 11.5.1
+      lru-memoizer: 3.0.0
+    transitivePeerDependencies:
+      - supports-color
+
   jws@4.0.1:
     dependencies:
       jwa: 2.0.1
@@ -5122,6 +5154,8 @@ snapshots:
 
   lilconfig@3.1.3: {}
 
+  limiter@1.1.5: {}
+
   lines-and-columns@1.2.4: {}
 
   load-esm@1.0.3: {}
@@ -5130,6 +5164,8 @@ snapshots:
 
   loader-runner@4.3.2: {}
 
+  lodash.clonedeep@4.5.0: {}
+
   lodash.includes@4.3.0: {}
 
   lodash.isboolean@3.0.3: {}
@@ -5159,6 +5195,11 @@ snapshots:
     dependencies:
       yallist: 3.1.1
 
+  lru-memoizer@3.0.0:
+    dependencies:
+      lodash.clonedeep: 4.5.0
+      lru-cache: 11.5.1
+
   magic-string@0.30.17:
     dependencies:
       '@jridgewell/sourcemap-codec': 1.5.5