fix(cabal-install): Suggest a concrete target when cabal run matches multiple executables

[zlonast]

fix: #12262

  Error: [Cabal-7070]
  The run command is for running a single executable at once. The target 'agent-cli' refers to the package agent-cli-0.1.0.0 which includes
  - executables: agent-cli, agent-telegram and eval-ghci-vs-bash
  - test-suites: agent-cli-test
  - benchmarks: image-preview-latency-bench and subagent-retention-bench
+
+ You need to specify which executable cabal should use. Try one of those:
+ - cabal run agent-cli:agent-cli
+ - cabal run agent-cli:agent-telegram
+ - cabal run agent-cli:eval-ghci-vs-bash

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