docs(cli): add mcpservers reference and refresh the command list

[ihopenre-eng]

Description

dapr mcpservers ships in CLI v1.18.0, but the CLI reference has no page for it, while every other command has one. The overview page's pasted dapr --help output also predates several v1.18 changes, and scheduler and workflow have pages that the overview never links to.

Verified against a dapr binary built from the v1.18.0 tag of dapr/cli:

$ dapr --help
...
  mcpservers     List all Dapr MCPServer resources. Supported platforms: Kubernetes and self-hosted
...
  scheduler      Scheduler management commands. Use -k to target a Kubernetes Dapr cluster.
...
  upgrade        Upgrades or downgrades a Dapr control plane installation in a cluster. Supported platforms: Kubernetes
  version        Print the Dapr runtime and CLI version
  workflow       Workflow management commands. Use -k to target a Kubernetes Dapr cluster.

Flags:
  -h, --help                  help for dapr
      --log-as-json           Log output in JSON format
      --runtime-path string   The path to the dapr runtime installation directory
  -v, --version               version for dapr

This PR:

• adds dapr-mcpservers.md, following the layout of the other command pages. Flags, defaults and examples come from dapr mcpservers --help on v1.18.0, with the defaults cross-checked against the flag registrations in cmd/mcpservers.go.
• updates cli-overview.md: the mcpservers, scheduler and workflow entries, the --runtime-path global flag, the dapr [flags] usage line, and the reworded upgrade description.
• links mcpservers, scheduler and workflow from the command reference list.

The new page links to the existing [MCPServer spec]({{% ref mcpserver-schema.md %}}) and [MCP how-to]({{% ref howto-use-mcpserver.md %}}) pages; both ref targets resolve to a single file.

Issue reference

N/A, documentation gap found by diffing the CLI reference against dapr --help on v1.18.0.

Checklist

• Docs
• Verified against the released CLI

[ihopenre-eng]

The CI workflows on this PR are queued at action_required and haven't started, so there are no check results to review yet. This is the first-time contributor approval gate for this repository.

Could a maintainer approve the workflow runs when convenient? Happy to rebase if anything has drifted in the meantime.

[sicoyle]

LGTM - thank you!!