Filter MCP tool visibility and invocation by the requesting API token's
(group, permission) scopes. tools/list now returns only the tools the
token's APIPermissions authorise; tools/call additionally re-checks the
scope in the dispatcher as defence-in-depth, so a session created with
one token cannot be reused to invoke tools that token never had access to.
The per-session filter runs at session-init via the StreamableHTTPHandler
getServer factory (which the SDK calls once per session, before caching
the *mcp.Server). The dispatcher check runs on every tools/call and
returns ErrScopeDenied, which the AddTool wrapper renders as an IsError
tool result.
Define the Op bitmask, the Resource struct, the package-level Register
function, and the Dispatch entry point that future tasks will use to
expose CRUD resources over MCP. No resources are registered yet.
Op carries the CRUD-op identity, knows its api-token permission string
(matching apiTokenRoutes exactly), and knows its tool-name suffix.
Resource.Inputs maps each enabled op to a pointer-to-zero of the wrapper
type the dispatcher will allocate and unmarshal into. Register validates
the resource shape and populates a tool-name lookup table so the
dispatcher never has to string-parse names like task_comments_read_all.
Dispatch threads the user from ctx, allocates a fresh wrapper, unmarshals
arguments, asks the wrapper to copy itself onto a fresh model via the
inputAdapter seam (which Task 4 will populate with real implementations),
and forwards to the corresponding handler.Do* function. The Do* calls go
through a swappable crudFuncs struct so the unit tests can verify
dispatch routing without standing up the database.