aep-136: clarify and fix kebab-case usage in custom method URIs

- Add explicit example showing kebab-case vs camelCase in guidance
- Fix Stateless Methods examples: :translateText → :translate-text
- Update translate.oas.yaml path and description
- Update translate.proto HTTP annotation

Closes #408

Author: toumorokoshi

aep/general/0136/aep.md.j2

@@ -25,7 +25,8 @@ apply consistently:
 - The HTTP URI **must** use a `:` character followed by the custom verb
   (`:archive` in the above example), and the verb in the URI **must** match the
   verb in the name of the RPC.
-  - If word separation is required, `kebab-case` **must** be used.
+  - If word separation is required, `kebab-case` **must** be used
+    (e.g. `:translate-text`, not `:translateText`).
 - The name of the RPC **should** be a verb followed by a noun.
   - The name of the RPC **must not** contain prepositions ("for", "with",
     etc.).
@@ -106,7 +107,7 @@ permanent effect on data within the API.
 
 {% tab oas %}
 
-{% sample 'translate.oas.yaml', '$.paths./projects/{projectId}:translateText' %}
+{% sample 'translate.oas.yaml', '$.paths./projects/{projectId}:translate-text' %}
 
 {% endtabs %}
 
@@ -116,7 +117,8 @@ permanent effect on data within the API.
   used.
 - The URI **should** place both the verb and noun after the `:` separator
   (avoid a "faux collection key" in the URI in this case, as there is no
-  collection). For example, `:translateText` is preferable to `text:translate`.
+  collection). For example, `:translate-text` is preferable to
+  `text:translate`.
 - Stateless methods **must** use `POST` if they involve billing.
 
 ### Usage in declarative clients

aep/general/0136/translate.oas.yaml

@@ -4,7 +4,7 @@ info:
   title: Library
   version: 1.0.0
 paths:
-  /projects/{projectId}:translateText:
+  /projects/{projectId}:translate-text:
     post:
       operationId: translateText
       description: Translates the provided text from one language to another.
@@ -37,7 +37,7 @@ paths:
             application/json:
               schema:
                 description: |
-                  Response structure for the translateText operation.
+                  Response structure for the translate-text operation.
                 properties:
                   translated_text:
                     type: string

aep/general/0136/translate.proto

@@ -22,7 +22,7 @@ service Translate {
   // Translates the provided text from one language to another.
   rpc TranslateText(TranslateTextRequest) returns (TranslateTextResponse) {
     option (google.api.http) = {
-      post: "/v1/{project=projects/*}:translateText"
+      post: "/v1/{project=projects/*}:translate-text"
       body: "*"
     };
   }