[bytebuffer] Rework ByteBuffer using templates

[clydebarrow]

What does this implement/fix?

With requests for additional functionality in the ByteBuffer class I've reworked it using templates and all in-lineable functions. This will:

1. Reduce the code size impact when ByteBuffer is not used to zero;
2. Reduce the code size impact to only those functions that are used in any given build;
3. Improve speed with inlining.
4. Allow new features to be more easily added.

The additional functionality requested (see #7625) was to allow puts and gets into the buffer without changing the current position. This is achieved with functions as below. In addition templated functions are added for all data types.

// Examples
void put_uint8(uint8_t value, size_t offset);
double get_double(size_t offset);

// Templated versions

T get<T>();
T get<T>(size_t offset);
void put<T>(T value);
void put<T>(T value, size_t offset);

Where T can be any of the supported types (8, 16, 32 bit integers, signed or unsigned, float or double.)

Now a component

The code has been moved from core into its own component. This will require any component using it to auto-load bytebuffer. The rationale for this change is to eliminate any possible code footprint when ByteBuffer is not used, and to facilitate CI testing.

Tests

Ideally this would be tested during CI with unit tests. This is currently not possible within the existing CI framework.
The test code only gets built during CI but it has been runtime tested on host and ESP32 platforms.

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
• host

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 32.25806% with 42 lines in your changes missing coverage. Please review.

Project coverage is 53.98%. Comparing base (4d8b5ed) to head (de08adc).
Report is 1525 commits behind head on dev.

Files with missing lines	Patch %	Lines
esphome/dashboard/web_server.py	11.42%	31 Missing ⚠️
esphome/writer.py	14.28%	6 Missing ⚠️
esphome/dashboard/core.py	72.22%	5 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##              dev    #7638      +/-   ##
==========================================
+ Coverage   53.70%   53.98%   +0.27%     
==========================================
  Files          50       50              
  Lines        9408     9764     +356     
  Branches     1654     1344     -310     
==========================================
+ Hits         5053     5271     +218     
- Misses       4056     4167     +111     
- Partials      299      326      +27     

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[probot-esphome]

Hey there @clydebarrow,
Thanks for submitting this pull request! Can you add yourself as a codeowner for this integration? This way we can notify you if a bug report for this integration is reported.
In __init__.py of the integration, please add:

CODEOWNERS = ["@clydebarrow"]

And run script/build_codeowners.py

_{^{(message by NeedsCodeownersLabel)}}