Auto-generate distro yamls + docs (#468)

# What does this PR do?

Automatically generates
- build.yaml
- run.yaml
- run-with-safety.yaml
- parts of markdown docs

for the distributions.

## Test Plan

At this point, this only updates the YAMLs and the docs. Some testing
(especially with ollama and vllm) has been performed but needs to be
much more tested.

llama_stack/providers/utils/kvstore/config.py

@@ -36,6 +36,15 @@ class RedisKVStoreConfig(CommonConfig):
     def url(self) -> str:
         return f"redis://{self.host}:{self.port}"
 
+    @classmethod
+    def sample_run_config(cls):
+        return {
+            "type": "redis",
+            "namespace": None,
+            "host": "${env.REDIS_HOST:localhost}",
+            "port": "${env.REDIS_PORT:6379}",
+        }
+
 
 class SqliteKVStoreConfig(CommonConfig):
     type: Literal[KVStoreType.sqlite.value] = KVStoreType.sqlite.value
@@ -44,6 +53,19 @@ class SqliteKVStoreConfig(CommonConfig):
         description="File path for the sqlite database",
     )
 
+    @classmethod
+    def sample_run_config(
+        cls, __distro_dir__: str = "runtime", db_name: str = "kvstore.db"
+    ):
+        return {
+            "type": "sqlite",
+            "namespace": None,
+            "db_path": "${env.SQLITE_STORE_DIR:~/.llama/"
+            + __distro_dir__
+            + "}/"
+            + db_name,
+        }
+
 
 class PostgresKVStoreConfig(CommonConfig):
     type: Literal[KVStoreType.postgres.value] = KVStoreType.postgres.value
@@ -54,6 +76,19 @@ class PostgresKVStoreConfig(CommonConfig):
     password: Optional[str] = None
     table_name: str = "llamastack_kvstore"
 
+    @classmethod
+    def sample_run_config(cls, table_name: str = "llamastack_kvstore"):
+        return {
+            "type": "postgres",
+            "namespace": None,
+            "host": "${env.POSTGRES_HOST:localhost}",
+            "port": "${env.POSTGRES_PORT:5432}",
+            "db": "${env.POSTGRES_DB}",
+            "user": "${env.POSTGRES_USER}",
+            "password": "${env.POSTGRES_PASSWORD}",
+            "table_name": "${env.POSTGRES_TABLE_NAME:" + table_name + "}",
+        }
+
     @classmethod
     @field_validator("table_name")
     def validate_table_name(cls, v: str) -> str: