support OPERA level-4 ZTD products for tropospheric correctioin (#1486)

* add basic entries to enable OPERA tropo support for parsing in MintPy

* first attempt on tropo_opera.py

* add opera functions to enable its method for tropo correction

* Added subsetting instead of full file download. This speeds up drastically

* fix: address review feedback (isort, memory scaling, docstring, CLI typos)

- Remove extra blank line after imports to satisfy isort
- Rewrite interpolation: cubic-lateral per height level then linear-vertical to reduce memory from O(npixels*ny*nx) to O(nz*npixels)
- Fix docstring in read_opera_total_delay_cube (one-level buffer -> bracketing)
- Fix CLI typos: Tropopsheric, trospheric, prerp, placeholder descriptions
- Add _ensure_ascending helper for axis/data orientation

* fix: pyupgrade f-string parens + add asf_search to requirements

- Remove redundant parentheses around f-strings (pyupgrade --py36-plus)
- Add asf_search to requirements.txt (needed for OPERA download)

* add fsspec[http] to requirements for OPERA remote subsetting

fsspec[http] includes aiohttp, enabling byte-range HTTP downloads
for efficient spatial/vertical subsetting of OPERA ZTD files.

* fsspec requires python=3.10+

* Implement geometry grid reprojection support for UTM TS

* fix: remove duplicate readfile import and trailing whitespace

* fix: sort imports (isort) in calc_zenith_delay_from_opera_file

* Refactor calc_zenith_delay_from_opera_file parameters

* Fix formatting in tropo_opera.py

* Refactor code for improved readability and structure

* Optimize calc_zenith_delay_from_opera_file function

Refactor zenith delay calculation for memory efficiency and clarity.

* Update authorship and improve docstring clarity

* Fix comment formatting in __main__.py

* Update author information and fix docstring format

* Fix docstring formatting in __main__.py

Removed unnecessary quotes from the docstring.

* fix: docstring D212 violations — summary on first line (Codacy)

* fix: convert multi-line docstrings to single-line to satisfy both D212+D213 (Codacy)

* cli/tropo_opera: minor print out msg re-org

* pre-commit fix

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Co-authored-by: sourcery-ai[bot] <58596630+sourcery-ai[bot]@users.noreply.github.com>
Co-authored-by: Zhang Yunjun <yunjunz@outlook.com>
Co-authored-by: Simran S Sangha <sssangha@ucla.edu>