Unify Signature with AbstractTele.Locns

[HoshinoTented]

Signature has a similar structure to AbstractTele.Locns, this PR intends to unify them.

Status: almost done, except class.

[codecov[bot]]

Codecov Report

Attention: Patch coverage is 91.66667% with 6 lines in your changes missing coverage. Please review.

Project coverage is 79.12%. Comparing base (4328b18) to head (a240b18). Report is 9 commits behind head on main.

:exclamation: Current head a240b18 differs from pull request most recent head 568bfc5

Please upload reports for the commit 568bfc5 to get more accurate results.

Files	Patch %	Lines
base/src/main/java/org/aya/tyck/StmtTycker.java	93.75%	1 Missing and 1 partial :warning:
...in/java/org/aya/syntax/telescope/AbstractTele.java	86.66%	0 Missing and 2 partials :warning:
.../src/main/java/org/aya/tyck/tycker/TeleTycker.java	80.00%	0 Missing and 1 partial :warning:
.../main/java/org/aya/syntax/telescope/Signature.java	90.00%	0 Missing and 1 partial :warning:

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #1122 +/- ## ============================================ - Coverage 79.17% 79.12% -0.06% + Complexity 3300 3292 -8 ============================================ Files 302 302 Lines 10012 10034 +22 Branches 1192 1195 +3 ============================================ + Hits 7927 7939 +12 - Misses 1425 1432 +7 - Partials 660 663 +3 ```

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