, bitcoin#25369, bitcoin#25617, bitcoin#25611, bitcoin#25736, bitcoin#25714, bitcoin#26612, bitcoin#27605, bitcoin#30464, partial bitcoin#25551 (univalue backports)

05e2091 merge bitcoin#30464: Fix MSVC warning C4101 "unreferenced local variable" (Kittywhiskers Van Gogh)
f00dc78 build: drop `-Wdangling-reference` GCC suppression (Kittywhiskers Van Gogh)
6d81d06 merge bitcoin#27605: Replace global find_value function with UniValue::find_value method (Kittywhiskers Van Gogh)
203a1c1 merge bitcoin#26612: pass named argument value as string_view (Kittywhiskers Van Gogh)
41eb3b0 merge bitcoin#25714: Avoid std::string copies (Kittywhiskers Van Gogh)
6f03a13 merge bitcoin#25736: Remove unused and confusing set*() return value (Kittywhiskers Van Gogh)
27cffb1 refactor: shed avoidable casts in Dash-specific UniValue-ret functions (Kittywhiskers Van Gogh)
32958da merge bitcoin#25611: Avoid brittle, narrowing and verbose integral type confusions (Kittywhiskers Van Gogh)
7802752 merge bitcoin#25617: univalue test cleanups (Kittywhiskers Van Gogh)
94bbbf1 partial bitcoin#25551: Throw exception on invalid Univalue pushes over silent ignore (Kittywhiskers Van Gogh)
d980870 revert: revert bitcoin#25464 (Reduce Univalue push_backV peak memory usage in listtransactions) (Kittywhiskers Van Gogh)
1e023e5 merge bitcoin#25369: Unsubtree Univalue (Kittywhiskers Van Gogh)
6b9e682 merge bitcoin#25249: Bump univalue subtree (Kittywhiskers Van Gogh)
b3443ee Squashed 'src/univalue/' changes from 6c19d050a9..de4f73ddca (Kittywhiskers Van Gogh)
9db7b12 merge bitcoin#25113: Bump univalue subtree (Kittywhiskers Van Gogh)
88f794f Squashed 'src/univalue/' changes from a44caf65fe..6c19d050a9 (Kittywhiskers Van Gogh)
b07e550 merge bitcoin#25153: Use getInt<T> over get_int/get_int64 (Kittywhiskers Van Gogh)
b1ae6f5 Squashed 'src/univalue/' changes from 2740c4f..a44caf65fe (Kittywhiskers Van Gogh)
1780961 revert: bitcoin#25464 (Reduce Univalue push_backV peak memory usage in listtransactions) (Kittywhiskers Van Gogh)

Pull request description:

  ## Motivation

  To get rid of the `-Wdangling-reference` suppression ([source](https://github.com/dashpay/dash/blob/f648039258d2192ec5e505721e34edaa0bda568c/configure.ac#L461-L467)) for GCC introduced in [dash#6639](#6639) by backporting the set of changes needed to backport [bitcoin#27605](bitcoin#27605).

  ## Additional Information

  * At some point, the contents on `univalue/` diverged from official repository ([bitcoin-core/univalue-subtree](https://github.com/bitcoin-core/univalue-subtree)), which makes updating the subtree a more difficult prospect.

    We realign the subtree by updating it to [`a44caf65`](bitcoin-core/univalue-subtree@a44caf65) (last sane commit, taken from [bitcoin#22646](bitcoin#22646), which was backported as [dash#4823](#4823)) and marking all merge conflicts in favour of the incoming update. This lets us do the final few subtree updates before it's no longer treated as a subtree.

  * To allow for subtree updates, [bitcoin#25464](bitcoin#25464) (backported as 001d7ba in [dash#6698](#6698)) was temporarily reverted and then reapplied _after_ the directory was unsubtree'd.

  * [bitcoin#30464](bitcoin#30464) needed to be backported to keep the whitespace linter happy (failed [build](https://github.com/dashpay/dash/actions/runs/16463979981/job/46536933377#step:5:119)).

  ## Breaking Changes

  None expected.

  ## Checklist

  - [x] I have performed a self-review of my own code
  - [x] I have commented my code, particularly in hard-to-understand areas **(note: N/A)**
  - [x] I have added or updated relevant unit/integration/functional/e2e tests
  - [x] I have made corresponding changes to the documentation **(note: N/A)**
  - [x] I have assigned this pull request to a milestone _(for repository code-owners and collaborators only)_

ACKs for top commit:
  UdjinM6:
    utACK 05e2091

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