fix: improve Name.isMetaprogramming

[JovanGerb]

This PR makes sure that identifiers with Meta or Simproc in their name do not show up in library search results.

For example, Nat.Simproc.eq_add_gt can currently be suggested by library search, even though it is an implementation detail. Additionally, there are various declarations in mathlib in the Mathlib.Meta namespace that we do not want to suggest.

[mathlib-lean-pr-testing]

Mathlib CI status (docs):

• ❗ Batteries/Mathlib CI will not be attempted unless your PR branches off the nightly-with-mathlib branch. Try git rebase 145a12104887190a20b016f81c73810b25da3e91 --onto 87ec768a509c45987a7d73258da0cc1ef047925c. You can force Mathlib CI using the force-mathlib-ci label. (2026-03-03 00:35:48)
• ❗ Batteries/Mathlib CI will not be attempted unless your PR branches off the nightly-with-mathlib branch. Try git rebase 145a12104887190a20b016f81c73810b25da3e91 --onto cda84702e9b31165f1f83c657b532f36f34e0bd0. You can force Mathlib CI using the force-mathlib-ci label. (2026-03-03 12:46:49)

[leanprover-bot]

Reference manual CI status:

• ❗ Reference manual CI will not be attempted unless your PR branches off the nightly-with-manual branch. Try git rebase 145a12104887190a20b016f81c73810b25da3e91 --onto cda84702e9b31165f1f83c657b532f36f34e0bd0. You can force reference manual CI using the force-manual-ci label. (2026-03-03 00:35:49)

[JovanGerb]

changelog-language