Correct typos and grammars in the docs directory #17798

As title, it seems that some typos, grammars and inconsistenct spelling should be fixed in the docs directory.

OpenHands AI triage

The following comments and acceptance criteria were added by the OpenHands AI agent.

Triage

The request is a documentation-only cleanup of spelling, grammar, and inconsistent terminology in the Markdown files under docs/ (README.md, DEVELOPMENT.md, SELF_HOSTING.md, architecture.md, ACP_AGENTS.md, CANVAS_EXTENSIONS_TESTING.md, DefenseClaw.md, TESTING_MATRIX.md). Scope is bounded to prose corrections; it is a cosmetic maintainer-reported cleanup with no user report, support evidence, or production impact, so it is prioritized priority:low. This repository owns docs/ (Agent Canvas documentation); no change is needed in OpenHands/software-agent-sdk, OpenHands/automation, or OpenHands/extensions.

Non-goals: no code, test, script, config, package.json, or src/ changes; no rewording of technical claims, no restructuring or reformatting of docs, no new documentation, and no changes to link targets, command examples, code fences, environment variable names, or file paths.

Acceptance Criteria

• Only Markdown files under docs/ are modified; no files under src/, scripts/, __tests__/, or any configuration file are changed.
• Spelling errors, grammar errors, and inconsistent spelling of the same term are corrected across the docs/ Markdown files.
• Corrections preserve the original meaning of each sentence (typo/grammar fixes only, no rewording of technical claims).
• Link targets, code fences, command examples, environment variable names, and file paths are unchanged.
• Internal links in the edited docs/ files still resolve to files that exist in the repository.
• Existing repository checks still pass on the change (npm run lint and npm test).