fix: inline content syntax

[farnabaz]

• Support inline markdown inside inline content syntax :inline[content **bold**]
• Add inline content as paragraph in block components (better compatibility with markdown directives)

:::block[p1]
p2

p3
:::

is equal to

:::block
p1

p2

p3
:::

[pkg-pr-new]

npm i https://pkg.pr.new/@comark/markdown-it@26

commit: 0d4b15e