add linear algebra and documentation

[apkille]

• Adds the following linear algebra functionalities:
  • Complex conjugate conj
  • Transpose transpose
  • Exponential of an operator exp
  • Vectorization of an operator vec
• Adds a guide documentation page for getting started with the package, now that we have extensive functionalities for creating, manipulation, and numerically translating expressions.
• Cleans up and adds docstrings.

[codecov[bot]]

Codecov Report

Attention: Patch coverage is 83.11111% with 38 lines in your changes missing coverage. Please review.

Project coverage is 73.88%. Comparing base (c9d8eed) to head (32658c9). Report is 1 commits behind head on main.

Files	Patch %	Lines
src/QSymbolicsBase/linalg.jl	82.63%	29 Missing :warning:
src/QSymbolicsBase/basic_superops.jl	59.09%	9 Missing :warning:

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #61 +/- ## ========================================== + Coverage 70.46% 73.88% +3.41% ========================================== Files 17 18 +1 Lines 650 804 +154 ========================================== + Hits 458 594 +136 - Misses 192 210 +18 ```

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