Obsidian Plugin: Toggle to mask tags

**What problem does this solve?**
I can't find a way to get the regex mask for the Obsidian plugin to ignore tags (`#`).
I'm assuming this is due to the actual logic not capturing the whole string.

**Proposed Solution**
A separate toggle in the plugin settings that masks out tags for Harper. I think this is something many users would prefer to have an option for. To avoid potentially breaking existing regex filters for users, I think handling tags separately makes sense. That said, any fix that solves my main issue I would be happy with.

**Examples**
I've tried the following patterns:
```
#[a-zA-Z0-9_-]+
\#[a-zA-Z0-9_-]+
#\S+
#\S+(?=\s|$)
```
The last two are the only ones that did anything, but the first of those managed to enable linting for code blocks, and the second matches against everything, tag or not. It's also possible that my regex filtering attempts are just incorrect.

**Component**
- [ ] Core engine
- [x] Plugin/Extension
- [ ] Other: _____

The issue identifies the Obsidian plugin as the component and provides regex examples; start by locating the plugin settings and existing masking path. Reproduce the reported behavior, then treat the work as done when an opt-in tag-masking setting works without changing existing regex filters, including the code-block behavior described in the examples.

Written by the indexing model from the issue text.