docs: fix typos, grammar errors, and stale URL across contributing docs

[farhann-saleem]

Description

Fixes multiple typos, grammar errors, and a stale documentation URL found across the contributing documentation and main README.

Type of change

• This pull request is a minor refactor, code cleanup, test improvement, or other maintenance task and doesn't change the functionality of Drasi (issue link optional).

Changes

File	Line	Before	After
docs/contributing/contributing-code/contributing-code-prerequisites/README.md	26	"we advice...depending on you OS"	"we advise...depending on your OS"
docs/contributing/contributing-code/contributing-code-prerequisites/README.md	100-102	Redundant paragraph (same sentence repeated twice)	Merged into single clear sentence, added missing "with"
docs/contributing/contributing-code/contributing-code-writing/README.md	10	"The get started, first ensure"	"To get started, first ensure"
docs/contributing/contributing-code/contributing-code-reviewing/README.md	5	"This page some contains guidance"	"This page contains some guidance"
docs/contributing/contributing-code/contributing-code-building/README.md	3	"several Makefile to build"	"several Makefiles to build"
docs/contributing/contributing-code/contributing-code-building/README.md	73	"To uninstall...using the following"	"To uninstall...use the following"
docs/contributing/how-to.md	15-16	Broken bullet point (line break creating extra * bullet)	Merged into single bullet point
readme.md	40	"for the community learn about"	"for the community to learn about"
docs/README.md	3	Stale URL https://drasi-docs.azurewebsites.net/	Updated to https://drasi.io/

Test plan

• Verify all markdown renders correctly on GitHub
• Verify no broken links introduced

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A couple of notes: since this is a docs-only cleanup with no functionality changes, no issue link is required.