[MISC] Update README.md

[deusebio]

Overview

I believe the README file was a bit out-of-sync and also required a bit of restructuring and rewording to align with the status of the projects, its aim and the recommended setup

Rationale

Also after discussing with some collegues, I believe the README is somewhat confusing and not as informative as it should. I tried to restructure/reword it a bit.

Checklist

• [x] The contributing guide was applied
• [x] The documentation is generated using src-docs
• [x] The PR is tagged with appropriate label (urgent, trivial, complex)

[github-actions[bot]]

Test coverage for 55b7ddf2f1dd097136729c74c980e86487992ddd

Name                      Stmts   Miss Branch BrPart  Cover   Missing
---------------------------------------------------------------------
src/__init__.py              83      0     34      0   100%
src/action.py               154      0     46      0   100%
src/check.py                 53      0     21      0   100%
src/clients.py               12      0      0      0   100%
src/commit.py                42      0     12      0   100%
src/constants.py              9      0      0      0   100%
src/content.py               50      0     10      0   100%
src/discourse.py            156      0     34      0   100%
src/docs_directory.py        33      0      8      0   100%
src/download.py              23      0      2      0   100%
src/exceptions.py            15      0      0      0   100%
src/index.py                128      0     48      0   100%
src/metadata.py              28      0     12      0   100%
src/migration.py             87      0     27      0   100%
src/navigation_table.py      65      0     20      0   100%
src/reconcile.py             95      0     44      0   100%
src/repository.py           283      0     88      0   100%
src/sort.py                  39      0     22      0   100%
src/types_.py               147      0     22      0   100%
---------------------------------------------------------------------
TOTAL                      1502      0    450      0   100%

Static code analysis report

Working... ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ 100% 0:00:02
Run started:2023-09-20 07:28:19.973783

Test results:
    No issues identified.

Code scanned:
    Total lines of code: 15681
    Total lines skipped (#nosec): 14
    Total potential issues skipped due to specifically being disabled (e.g., #nosec BXXX): 0

Run metrics:
    Total issues (by severity):
        Undefined: 0
        Low: 0
        Medium: 0
        High: 0
    Total issues (by confidence):
        Undefined: 0
        Low: 0
        Medium: 0
        High: 0
Files skipped (0):