[config] Improve error reporting

[clydebarrow]

What does this implement/fix?

This fixes two problems with error reporting when processing a YAML config;

1. Errors in lists report the list index instead of the key for the list:

    - id: bdr_style

      [grid_cell_x_align] is an invalid option for [4]. Please check the indentation.
      grid_cell_x_align: stretch

2. When emitting errors in a long config section, the entire section is printed. If the error is close to the beginning this scrolls it away. This is particularly an issue with LVGL where the lvgl: config section can be hundreds of lines long. Deal with this by stopping the output a few lines past the last error.

3. Also fix a minor typing hint error - ConfigPath and ConfigPathType are used inconsistently (note: it is likely that ConfigPathType can be removed completely, did not look into that fully.)

Types of changes

• Bugfix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Other

Related issue or feature (if applicable): fixes

Pull request in esphome-docs with documentation (if applicable): esphome/esphome-docs#

Test Environment

• ESP32
• ESP32 IDF
• ESP8266
• RP2040
• BK72xx
• RTL87xx

Example entry for config.yaml:

# Example config.yaml

Checklist:

• The code change is tested and works locally.
• Tests have been added to verify that the new code works (under tests/ folder).

If user exposed functionality or configuration variables are added/changed:

• Documentation added/updated in esphome-docs.

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 20.00000% with 8 lines in your changes are missing coverage. Please review.

Project coverage is 54.21%. Comparing base (4d8b5ed) to head (876b2a9).
Report is 583 commits behind head on dev.

Files	Patch %	Lines
esphome/config.py	20.00%	8 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##              dev    #6736      +/-   ##
==========================================
+ Coverage   53.70%   54.21%   +0.50%     
==========================================
  Files          50       50              
  Lines        9408     9594     +186     
  Branches     1654     1691      +37     
==========================================
+ Hits         5053     5201     +148     
- Misses       4056     4069      +13     
- Partials      299      324      +25     

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